Well, if they don't want Pokemon being associated with gambling, then they've failed at it miserably (given our use of dice + the video game creators' constant spamming of gambling centers in RBY=DPP lol).
Still, I shouldn't let that comment about dice take over the concern about PCL's intent in the mechanics of flips and RPS. If it turns out that, sure, they couldn't car less about randomization, then that puts this discussion in a completely different light.
*shrug* Seems like it matters since that's the only reason coins are given special treatment. Coins are special cause Japan says they are.
Aside from their reasoning, it really just makes logical sense. You need a randomizer with 2 outcomes, and there happens to be just such a thing that has been around for thousands of years, called a coin. If they wanted a randomizer with more than 2 outcomes they probably would've chosen a different randomizer.
Honestly, a coin is just a two sided die.