These threads about public pooping and open drug use show that a lot of people seem to equate their feelings of discomfort with feelings of danger. Just because something is upsetting to see doesn't mean it's dangerous. I've seen people relieving themselves on the sidewalk and have never once thought that they were a danger to me or my family. It's gross, but seeing gross things never injured anyone.
Did you read what I wrote? My entire post was about how quality-of-life issues and crime/safety issues are not the same thing.
While stepping over poop or smelling urine on the street doesn't hurt me, it doesn't exactly make me happy to live here either.
(Fortunately I moved out of SoMa and into a nicer neighborhood a few years ago, so I don't have to deal with sidewalk piss and shit on a daily basis anymore.)