I see these guys all over Castro and after living in SF for so long, I don’t blink an eye. Shriveled up old man penis and overly tan skinned ( no lines of course) is a common site in the Castro district. One health concern though. I see “them” sitting bare-ass on pubic chairs and seats. Is that hygienic? I mean get a mental picture and think about it next time you set your cell phone on a public chair or seat. This also applies to assless chaps ; bare-ass in full contact of seats.
http://www.sfweekly.com/2010-12-01/news/nudists-public-nudity-castro-san-francisco/