Not a purchase that I made, but when I was living in Jersey City I got onto the elevator one day and there was a guy already in it with an absolutely enormous case next to him.
I asked him what it was and he goes “so this is kind of embarrassing but a few nights ago I got really drunk and decided it would be a good idea to buy an upright bass. I’ve never even touched one before and have no idea how to play it, so now I don’t know what I’m going to do with this.”