"They're just doing what they must to survive" doesn't justify the street behavior of san francisco vagrants any more than it justifies a hungry dog ripping the face off a kid.
Do you live in a neighborhood where you deal with the homeless and mentally ill on a daily basis and at all hours?
Do you step in shit? Are you spit on? Accosted? Have your roommates come home with phlegm and spit in their hair? Have you left your apartment to find a man's face pressed against the window, yelling "You look like you've been waiting to eat my ass your whole life"?
I'd need a yard to put the Y in NIMBY, but all I have is a feces-caked grate that I routinely kick people off of so I can open the door and get into a street that stinks of piss. Sorry if you're bummed that I'm interrupting their pill sales.
Live and let live doesn't cut it here, not for me. The idea that these people should be left alone regardless of the blight and destruction they cause to public spaces is short sighted and wreaks of "I don't actually experience this problem".
The homeless are struggling. They need help. But they're a scourge, too, and I'm sick and tired of people boo-hooing about how they're just trying to survive as the streets in this city rot from their presence, as though their being in pain makes it acceptable that they erode the quality of every public space in the city. It is not acceptable.
The solutions we have for homelessness and its associated ailments are weak, and need to be better. They need to be rooted in generosity and upward mobility. I completely agree. I'm all for huge city spending on building, and on every conceivable social program, especially for mental health.
What I am not for is turning a blind eye to the realities of homelessness' effects on the city in the mean time, and to distance the crimes and destruction from the individuals who commit them.
You do not get a free pass to fuck up the world because your life sucks.