I tend to people watch in crowded areas which is more interesting to me especially if my wife forces me to go clothes shopping. 2 gyms ago my wife and I noticed this 1 woman on a treadmill who was quiet, but her head was always looking all around taking everything in which we always thought was odd. Now at the current gym I do half my runs on a treadmill and I'm looking all around like she was, when I'm not watching the tv attached.
Almost all runners have OCD so I tend to not mess with a fellow quirk. There was 1 day I was in a library checking out dvds. There was 1 guy carrying a bunch of them, but had a system of methodically going in the correct order of the alphabet row by row. So I stood still looking at the next section and of course he bumped into me. Rather than apologize he just gave me a dirty look, and I let him be so he could continue his system.
LOL, I love people watching!! Was just doing it today!
And by the way, I did some reading awhile back (when I saw my son do it a few times!) that people who eat boogers statistically have a better immune system than people who don't, because all the bacteria and viruses that your nose collects is then transferred to your stomach and so your body grows an immunity to them, kinda like a vaccine