Given the flow of people between the bits of the Bay Area and Eastern Mass with residents-only parking, this isn't a big surprise, but the stickers still make me smile when I see them.
Question for you Bay Area people: have you folks noticed many cars with Somerville/Cambridge/Boston residential parking permit stickers in their windows? I haven't really been looking out for them when I've been driving around the City or the East Bay. Or is the flow of cars one-way, because of CARB smog requirements? Or something else?