Some do - I'm not really sure why it's relevant though, if you agree with the host that you'll keep the place tidy, and you don't, you're in breach of your agre

Some do - I'm not really sure why it's relevant though, if you agree with the host that you'll keep the place tidy, and you don't, you're in breach of your agreement. It's not just a matter of throw money at it since it can impact business, especially for popular destinations or high tourist times when the places are booked solid for a few months. Having to be out a few days can throw off the schedule, which is crappy for the next guest and crappy for the host. It's not just about the initial money - really bad messes can affect more than just the host and cause problems you can't just solve with money. Too high of a deposit and no one will rent, but if someone's mess disrupts, then the deposit isn't enough to cover losses.