Why not? And anyway, they could at least try to do it in semi-privacy - maybe behind a building, or in the bushes, or something. No, it seems almost deliberate to me, or alternatively so zonked out on drugs/malice that they just couldn't give a damn. Either way it's not just a lack of facilities. We've all been in a strange part of the city we don't know well, no toilets anywhere and busting to go. We all somehow found some kind of semi-acceptable solution that didn't involve shitting on someone's fence.

I have no idea why it's different in SF but these things just don't happen elsewhere, so there must be some reason for it.