I think this would be a lot more popular if the site admin didn't need to take "a few percent" out of the bet pool. I don't see why that's necessary, it's like you're just trying to get rich with minimal effort... agar.io is completely free and can sustain itself even with a large number of players... In fact there's nothing stopping anyone from making a free version of chopcoin.io that uses ads to pay for its server rather than taking a huge chunk from the bet pool and reducing people's winnings for no reason.