I don't understand how anybody can say that they have a hard time thinking somebody can be so stupid as to (insert stupid thing here). Years ago, I worked out at a gym and there was a cop who worked out at almost the exact same time I did every day. He was a complete jackass, douchebag, moron. One day he was sitting on a piece of equipment shooting the bull with another guy. He'd been sitting on it for at least 15 minutes and laughed as people who were circuit-training (working through the machines in a certain order) had to skip that machine. He'd point at them and chuckle to the other guy as they skipped it. Everybody knew how he was and just tried to ignore him. Finally, a woman in her 40's who apparently didn't know him asked him in as sweet and polite a way as is humanly possible if she could use the machine. He blew up, called her a fat-azz (cuss word), told her he'd been working out there since before she knew what a (cuss word) weight machine was and told her to get off his (cuss word) back. In front of at least 30 other people. Loud enough that there's no way that anybody DIDN'T hear it. She was stunned and backed away and started crying.
Can you imagine somebody being that stupid? Well, it gets worse. He was still kind of walking towards her and seemed ready to continue yelling at her. Bailey, the guy I was working out with, stepped in front of her to block him. I stepped in front of him and told him to back off and told him he was being something I can't repeat here. He starts cussing me and tells me that he knows I work on the road for my job. He tells me that I need to mind my own (cuss word) business because he can make sure I get a traffic ticket every day for the next (cuss word) month. He asks me how long he thinks I'd be able to keep my (cuss word) job once my license got revoked. This is in front of 30 people!
I laughed and asked him how long he thought it would take the tickets to be thrown out when all these people testify that they heard him threaten me with them.
Things people do surprise me, but never because I can't imagine a certain level of stupidity. As Einstein said (allegedly), "Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."