How does supply side defection work for airbnb except in very edge cases, such as a long term rental. Even then it turns into something like apartments.com
It works since Airbnb is mostly there to hook you up and protect from crazy people's wanton destruction, so once you know you're dealing with safe people and you've gotten the review, eh.
Wouldn't really be worth the penny-pinching, except people tend to forget about the long-term booking discounts and actually end up paying more than they would've just using airbnb.