There's one secret achievement (The Chariot, I think it's called) that I haven't gotten yet. According to the achievement FAQ for this game, it says that one of the ways to get rid of the zombies is by boosting into them. Aside from using the shoes, would using the mini-turbos (after when you're done drifting if you have at least have flames) work as well?
I got a fever..... and the only prescription is more cowbell.
No - drift boosts don't cause damage, you'll just spin out if you hit a zombie. Either hang around on Sewer Scrapes in the open-air section just after the hydra, staying beside the item boxes and just kill the zombies over and over, or else use Mission 41, where you have infinite boxing gloves and can hit zombies with them instead of your opponent.
And the Lord said unto John, "Come forth and receive eternal life." But John came fifth and won a toaster.