[wdb]

What I am always curious about are all these rentals on AirBnB owned by the people renting it out? As I am renting myself and my rental agreement clearly states I can't underlet it: "Not assign, underlet or part with or share possession of the whole or any part of the Property."

Ain't this a normal item in an agreement? How does this work? Are they just breaking their agreement?

[GuiA]

A fair amount of them are breaking their lease agreement, or doing it in violation of local laws. Walking down the Mission in SF, you'll find a fair number of orange sheets taped to apartments from the San Francisco Office of Short Term Rentals, informing the tenant that they are in violation of the SF Administrative Code Chapter 41A.