At times it's funny when you don't get it. Ever had that happen? You just get disrespected for no reason. I'm guessin' there's more than a few moments like that in your life and when you begin to recall them I'm sure you'll see the potential funny material there as well.
Most negative altercations between humans are fertile ground for writing about if you're looking for humor. Especially if they're small, such as; dealing with lines of any kind, waiting for service of any nature that is slow, dealing with repair people, complaint counters, whacky relatives or customers,.