Are they saying that you should live near where you work?  I understand the frustration of San Francisco rents, as I have had all 3 of my kids live there within the last 2 years.  If they really want to ease the housing shortage:  Don't allow renters to sublet!  If one has rent control, and pays $1,200/month, but they would have subletters  tripping over each other to pay $3,000/month, would anyone ever let that apartment go? No, they will rent it out, and pocket the extra cash, and they've been lucky, in that the market has never crashed, and has only increased.  All these old tenants holding the properties and subletting, I believe are at least one of the major reasons for the housing shortage in San Francisco.

That type of subletting is already illegal in SF. You can't sublet for more than a proportion of the master tenant's actual rent.  If you do, the Rent Board will force the sublettor to refund the difference.

Maybe it's not enforced very well.  My son and his roommate rented for over a year a complete 2 bdrm flat, from someone who was the actual renter.  They were not allowed to put their name on the mailbox, or be on the lease, or contact the landlord.  Another person I know, rents a 3 bdrm rent control flat, makes a 6 figure income, and sublets on AIRBNB 1 room, drops their rent to $0 or even turns a profit.  It goes on, and I guess the newcomers are too thankful to finally find a place they don't turn it in.  It's brutal shopping for a apartment/room in SF, you could show up to an open-house, along with 50 others all wanting the same room.

They don't exactly make inspections of leases... you need to enforce the law for yourself.  The SF Tenant's union can help.

Not sure about the legality of airbnb in SF.. I've heard arguments both ways, but an airbnber isn't a subtenant and wouldn't be covered by proportionality.

The legality of Airbnb has not been tested in SF, but the type of abuse of the spirit of the law that Janill talks about is definitely happening and Airbnb is benefiting from it.

And yes there is a housing shortage in SF and this makes it worse.

Mind you, there are also people who protest the bus itself:

http://pandawhale.com/post/6577/the-hidden-bus-routes-of-silicon-valley-and-san-francisco-google-bus-dominates