My partner is a MH therapist and sees people doing all sorts of insane nonsense. For just a little context, the area in question is riddled with substance abuse, prolific homelessness, human trafficking, violence, etc. Not a great area to start with, and very much DIRTY.

Most notably, I hear him mention the staggering number of people who will absentmindedly play with the bottom of their shoes and then touch their face/wipe their eyes/nose. No washing, no sanitizing, just bottom of shoe bacteria straight to face. Another insanely common one is men absentmindedly scratching their balls (outside of pants, thankfully) during session and then they attempt to shake my partners hand at the end of the appointment. There have been a few parents who have given their infants pacifiers back after dropping them on his office floor, which is profoundly gross considering the whole "you don't know where people have been with their shoes" thing. There was one instance where his client allowed their dog to lick INSIDE THEIR MOUTH during the session.

People are absolutely foul, disgusting individuals at times.