Bad? Yes, it has been done before, but it is an original and hilarious twist on something that should be boring. Every time, and I do mean every time, I activate a can of beans or drop a turd on the raceway, my wife and I laugh for a good 10 minutes. Hell, every time I drop off the course and yell, "oh crap" we laugh as well.
Seriously, anyone who finds this disgusting to the point of down-ranking their score needs to take a chill pill. The gameplay is solid, the graphics are adequate to the needs of the game, and it kept me interested for a solid 4 hours. I gave it a 9/10, and I challenge anyone to explain to me why it isn't.
Really fun game, way underrated at the moment. Sure it's a bit of a childish or bad theme maybe, but the concept works, it's like some kind of variant of mario kart and it works pretty good for a flash game... The option to unlock stuff with coins collected in races is also good...