I am a Yugioh Player only,I have played in one Pokemon Tournament and I have an account on this site, because my little brother plays Pokemon. I live in the Tri-State Area in New York specifically, where thievery is the norm. I am Hispanic and have a troubled upbringing, but I have dealt with numerous people, different societies allowing for me to understand different groups of people. I point out this in case some of the things I write sound racy that in no means am I against any particular person. I just wanted to put this as an intro as a frame of reference for you.
For the people who have lost things, I feel your pain, but it should be a wake up call for everyone. We all have stereotypes and we should use it in making decisions regarding one's safety. If you see a group of minorities approaching you or you feel uncomfortable with a group of people surrounding you looking at your binder, just put it away and walk towards your friends. In the one tournament, I went to, the Pokemon players were to me no way intimidating. I recognized a few Pokemon players who also played Yugioh, who are known thieves in NY or associate with thieves on the daily. One of the thieves had tons of uxies unsleeved,Uxie Lv X's, etc. indicating these were probably stolen. He was with like two friends,so he couldn't really jump anyone effectively, but of course he can swipe a bag or two, or take a few cards when someone isn't looking. The problem is no one at that tournament paid any attention to that fact, the atmosphere at the tournament was lax. This is what all card games should be like, no fear of any violence towards you, but obviously there are always some bad apples seeking a few quick bucks.
Another thing, I noticed was that most of the players were white. Even though, I grew up in a poor neighborhood, I did attend a prep-all white High school, so I have dealt with both groups (preppy white kids and ghetto minorities). The one thing I do notice is that when a minority is being loud and boisterous, white kids tend to tense up in a situation. Even though kids that grew up in poorer upbringings, they are fairly knowledgeable in social settings, meaning they know how one is feeling. This is how they can steal from you, by surrounding you in a group asking you to see your binder, try to take cards out of your binder and put it on the table while you look at their stuff. You feel more inclined to abide by them in fear of them being louder. This isn't simply a race thing, it is all about one's confidence in themselves.
Typically Pokemon and Yugioh is played by people who aren't the most social individuals,hence how they started playing this game, since typically the social kids played the sports or went to the parties. Obviously, this isn't the case for everyone(I am not speaking narrow-minded), but this is the stereotype and some of the individuals fit the bill. If you are socially awkward, you tend to maintain that growth, so when put into awkward situations, those fears are quite evident. Another thing is you do not want to stir trouble with minorities. Society dictates that minorities must be treated differently to appease them, which I find is wrong. African Americans are raised to be proud of Black Power, while Whites tend to be proud of their specific heritage. White Power's connotation in society is seen as a hatred towards minorities, deeming it unacceptable. With this outlook on life, one doesn't want to stir trouble with minorities(who typically are the thieves at events). I have seen this happen at Neutral Ground, a famous New York gaming store which has closed down due to the numerous thievery cases as well as high rent, where a Hispanic male was accused of stealing by the White owner. The Hispanic male immediately made this a race issue, while the White owner told him to rest assured it was simply eye witness testimony. The White owner simply banned the individual instead of seeking any legal punishment, so the individual goes freely knowing he stole. The moral of the story is don't see things as a color, but see it for what it is. If you feel pressure, pressure them back; don't let anyone walk all over you.
Yugioh thievery is orchestrated. I do not know the Pokemon scene all too well, but from what it seems its just Catch and Go. Yugioh thieves, which I know most of the groups and their individuals, since they mostly reside in the Tri-State Area. They are in numbers, carry knives, and aren't afraid to fight to some degree. You have to understand that thieves are sly individuals, but aren't confident at all. There is a reason, why they go in groups, its because they aren't confident in their fighting if faced with retaliation. I travel to tournaments with four people mostly, but always with my best friend. Many people know of him as being a strong, loud black guy, who knows how to fight. No thief ever dares to steal from me or from him, because some have heard of the time when 14 guys tried to jump me and my three friends where two of the assailants were stabbed and one was put into jail. How do 14 people fail to rob 4 young teens? They can't really fight, hence why they just try to overwhelm you with numbers or carry weapons. This brings up another point, thieves are stupid. They live in the moment, not really thinking of the consequences. They think of how they can make a few bucks. Without really thinking about what if someone they try to rob has a weapon and threatens to use it on them. A case happened once in Neutral Ground, where a few young teens tried to rob a middle-aged man of his Yugioh cards since he carried an expensive Championship card worth $1500+. The man carries a licensed gun, so obviously he let them off the hook, but this shows that thieves aren't necessarily thinking of what if.
Now why is it so easy to steal in Pokemon? There are many easy targets. It is a lax environment, the player base isn't really aware of the presence of thieves, and they can't fight back. Thieves will not attack PokeMoms/PokeDads, because those are adults, but they will seek easier targets like Juniors/Seniors binders/decks/bags. Pokemon has young kids with competitive decks meaning they are expensive, so you steal one or two decks from easy targets you are looking at $200+ for nothing. Thieves don't see any wrong doing from stealing from a kid, because they are already stealing. They won't test individuals, who they feel can present a problem.
I am not saying only minorities steal, because some white players do steal, but the one group who tried to do it at 2008 Yugioh Nationals on a friend from Brooklyn, resulted in his group being outnumbered in a span of 2 minutes 20 vs 8 and one of them going to the hospital, after my friend thrashed him not knowing he was a football player and a boxer. Also thieves steal because they are lacking something. Minorities who do steal often grow up in poorer areas where money was a necessity, so instead of getting jobs and doing an honest living, might as well get a few quick bucks with little to no effort. White kids do not feel the need to steal, because they are often in middle to upper class, where money isn't a necessity all the time. Also different moral upbringings plays a role. My father is a deadbeat, my mother is in huge debt, so I am not given money by my family, but I do work for money or play Yugioh players for cards/cash . I try to obtain my money through just means, plus I use my money when needed. i do not feel the need to spend money on myself unless its out of necessity. Rap/Hip Hop culture dictates the need to gain money and acquire women and buy all that crap. Basically continuing the cycle of ignorance.
To conclude this post, pay attention to your stuff, be wary of individuals around you, use stereotypes to judge others when they are looking at your stuff, and do not be fearful if pressure challenge others.