I can't actually comment on the gameplay of it since I really did compete against anyone. However, the game mechanics do work though they do look a little cheap (the character just moving rapidly back and forth to run and moving rapidly back and forth to eat). The landscape looks very good. I think this would be a good game, but it relies on the inclusion of other players. In other words, less players equals less fun.
I suggest putting in a short message that says "warning, do not eat poop in real life" or at least a disclaimer so you don't get sued because kids might play this game and yes, one of them might be dumb enough to refer to this as their reason for doing something stupid.