There are two factors that make it difficult to throw things away - age and distance. By distance, I mean that the object has come from far away. If something is old or comes from an exotic place, it doesn't matter how useless, pointless or frankly unpleasant it is, it's difficult to get rid of it. I suppose it's a question of replaceability - if all you need to do to replace an empty tube of toothpaste is go to Tesco, it somehow makes the empty tube of toothpaste less valuable than one that one would need to go to Tokyo to replace. Despite the fact that they are both tubes of toothpaste, and now they are empty. There is an argument that if you would have to go to 1653 or Alpha Centauri to replace it, any object is valuable, but that's quite a moot point as I have nothing that fits either of those descriptions.

This is a case in point - Japanese toothpaste tube. Very cool, which it helpfully says on the packaging along with a number of other things that I can't read because they're in Japanese. All the same, no matter how cool it is, it's still, sans toothpaste, garbage.