The apartment building I live in here in NYC forbids people from using airbnb and similar services. I'm glad because I don't want to worry about a flux of transients in my building. Some laws may be problematic to vc/startup folks but I'm glad they exist because they protect me.
I feel like the word transients is too often used to refer to homeless people. My impression is that AirBnB caters primarily to upper middle class vacationers. Are they really a problem? This is a serious question as I've never had to deal with this sort of problem.
The vast majority of NYC leases forbid subletting of any sort. Leasing or subletting to someone for under 30 days is illegal in NYC if you don't have the proper permits. There is a loophole in the law that makes it legal for you to rent out a room within your apartment for under 30 days while you are present in the apartment, though most leases forbid this as well.