It's a strange kind of humor. You go out into the world and do things that you know (or presume) will get attention, but you yourself have to maintain composure, feign obliviousness to it all. But secretly, you're getting off on how ridiculous it all is, and therein lies the humor.
I used to do a lot of stuff like that, just do wacky shit and chuckle to myself at the imagined responses. Then I kinda got tired of never actually getting to see/hear those responses or even find out if there were any. No real payoff, it seemed. I was doing it for my own amusement, and I guess I just moved onto other things.