Earlier quoted context omitted.
Question: Why does Airbnb need to deal with this at all? I mean, if these apartments were being advertised on craigslist or local classifieds would you think they need to deal with it?
The classifieds don't provide comprehensive listings of short-term vacation rentals. But I'm not saying Airbnb "needs" to deal with it. I'm saying they "should" decline listings from people who don't own their property absent some documentation of consent from the landlord of that property.
Having AirBNB try to determine if every single renter/homeowner has the rights would be a nightmare.