As a fellow developer of online multiplayer games, I found there are certain defined limits to what you can charge players for, and what you should not. This is definitely crossing that limit. Charge players to buy things in the game that are fun, but not useful. Decorative items, items that let them personalize their characters BEYOND the free-to-plat limit. I think of ROTMG as a good example. You don't need colors to be as good as everyone else in the game, but they are their to make you stand out for the crowd.
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