What Planet are you living on? Because here on Planet Earth Prize Penlties are issued when an unfair advantage is produced to compensate a player for the problems.
A game lose is generally issued when a game is virtually unfixable, and little to nothing can be done to restore the game state. If a player is caught purposefully cheating they may be issued a game loss (as the game state is broken) or be issued a DQ. Game losses and DQs don't happen at the drop of a hat, and meant to be used for worst case scenarios. Also restarting a game can eat up large amounts of time and can cause other problems. Finally issuing a game loss for trying to seek proper mediation for a problem is not 'rule sharking.'
Yeah, that's called rule sharking. A game can be fixed if the time is put into it. Forgetting to set prizes should not be a game loss. Ether let them set their prizes from there or restart the game.
While your right on weather or not you find the prize penalty is too severe or not that's what those in charge of the rules think is the best tool to fixing the majority of problems (that and time extensions). I'm not going to try explain why, as I may be off on my reasoning, but drawing cards is probably viewed as more of a destructive thing than a helpful tool in their eyes.
It depends. I would rather draw a card or 2 then take a prize card or win a game because of a game loss.
As described above judges do make mistakes in their judging at times, but you are free to appeal to the Head Judge if you are uncomfortable with the judges ruling. Judges have a lot on their plate at times, and can be wrong in their evaluation of a situation, because of a number of reasons. But in the end judges are left with responsibility to judge due to the trust made between PTOs and Pokemon as they have separated themselves from the heard, and should hold no bias on a match. A player on the other hand is influenced by their games, and lack the connection of trust to the PTO, and Pokemon.