One time I was waiting in line at the pharmacy at Walmart and some old guy (75+) was pitching an absolute fit with some poor pharma employee over some vitamin they didn't stock.

After carrying on and berating this poor girl for a solid 5 minutes, he finally walked off. A couple minutes later, he was back in her face again pitching another fit. Because he found something he wanted. And apparently that was also bad.

At that point I told him to shut up. He gave me a dirty look and said it was none of my business. I told him he was making it everyone's business the way he was carrying on. He finally shut up and left.

I'm sure he pulled the same shit again a week later. He was definitely the type.