In fact, these people will sample that can of spray paint anywhere.
And then, after they've decided they like the color, they will put the can they've just used back on the shelf and grab a new can. Why would they want to buy one they've just used?
Yesterday I had one of these morons ruin a can of specialty spray paint. He was a pharmacist, I could tell because of the mortar and pestle on his coat, and he was looking at a can of hammered titanium. I asked him if I could help him. He said "nope," and broke the lid off of the can so he could sample. After covering the side of a paint box he said "I don't like this," and put the can back on the shelf. It didn't seem to bother him that he'd broken the lid off. Instead, he grabbed a can Chrome from the shelf and said, "I'll take this," and left. I took the can of paint up front and marked it down because customers don't by cans of spray paint with broken lids. As I've been typing this I've realized this guy was not so much of a spray paint moron as he was a spray paint asshole. I wonder if he's as thoughtless when filling prescriptions?