You would be hard pressed to find any item that someone doesn't collect. I knew someone who collected paper clips and another who collected copralites. Those mugs are hand decorated so in a way they are one of a kind items and works of art. I've seen them go for thousands. I collect minerals so far be it from me to comment on collecting anything. I know folks who spend thousands on rocks. Maybe gold or platinum or diamonds but they'e rocks after-all.