What do you mean by house edge?  In a game like this, there is no house edge.  The house is not playing in the game, it is merely providing a platform on which to play the game.  We charge a 4.5% fee (which is fully disclosed), which pays for hosting.  Everything else is based on the other users playing against each other.

This is a ponzi game, not a ponzi scheme.  It is not illegal to play with, and 75 cents is not nearly enough for law enforcement to take a stance either way.