Back in the mid 1980s, I lived relatively close to a major street in a large city. I got bored with the routine public safety radio traffic and one day I began scanning through some UHF frequencies looking for something different.
One fairly active channel popped up during business hours and there were a lot of derogatory comments about the customers between employees on an itinerant UHF frequency. Comments about ugly clothing, bad credit, lack of personal hygiene, taste in autos, ageism, sexism, and every other kind of derogatory comment possible. After borrowing a portable scanner and riding my bike around the area while listening, I discovered that it was a prominent auto dealer whose management and sales people who weren't as fond of their customers as their ads claimed and chose to talk about it on a clear frequency.
It was rather interesting and some of the comments were as brutal as anything Andrew Dice Clay would blurt out during his heyday.