Crazy8, I can sort of answer your question from another angle, being one that creates collectible bottles myself. It started about 5 years ago when I made up about 20-25 of what we now call the "Batch #1's". They went for $20. Almost overnight, these things were an enormous hit. These Batch #1's, of which there are about 8-9 known to still exist, have gone for over $500 in private auctions. Honestly, I was stunned, but also happy in a weird way. We began releasing new versions of the "Batches" and they have become a quite sought after collectible. The most recent one, the "Batch #5", went for around $125 retail. We put about $100 into the making of it, so it's not about the money, it's about the passion of making the evil stuff, and pleasing people with a cool addition to their personal "Shelf of Doom".
I have been collecting Blairs stuff for years now. Why? Not sure. But I do enjoy looking over at the shelf of his stuff every now and then in my office, it just looks really cool.
Like others have said, beauty is in the eye of the beholder. I don't understand why people would pay tens of thousands of dollars for some paint a dead guy put on a piece of canvas, and I think beanie babies look really cool flying out of a spud gun, but collectors of those things would probably think I was insane for paying a couple hundred bucks for a bottle of hot sauce, to each his own.