To Chuck's point: I started collecting old computers because I found I still had digital information from 30-40 years ago - programs and documentation - in my possession, and I was curious to revisit it. Partly that was due to wondering about how it compared with modern offerings - how far things have progressed, as it were - and partly because, in my untutored ignorance of 30-40 years ago, most of it was beyond my ken. It wasn't what I did for a living and there was only so much time to spend learning. Call this a second childhood.
But to your point: I'm not a collector of equipment that is rare, for the sake of its rarity, or valuable, for the sake of its value, but of things that interest or fascinate me that I want to better understand. I never have seen a reader or a punch in operation but one day I'd like to find one; I still remember the CP/M terms and the mystery they held for me. I consider myself a caretaker: if I have collected something I want it to work, and I will do what I can to restore or improve its operation. My chief obstacle is my lack of knowledge, particularly in the field of electronics. Sometimes I make fatal errors: Mine is a pretty small and mundane lot.
I have never sold anything I acquired, but I have thrown away a few things that I thought were unworkable, just for lack of knowing where to find repair. On the other hand I have given quite a number away, if I thought the recipient could use them. Some might be considered classics today.
I guess all that puts me in category two: A Vintage Computer Collector who is the owner of that equipment can dispose of it accordingly. But the people who want to make fishbowls out of their 5153 monitors are misguided, in my opinion and the people who make their living "flipping" items on eBay are, at best, a necessary evil and, at worst, (expletive deleted).
My thanks to all who frequent this site and offer their wisdom and experience, making possible for me this fascinating endeavor.
-CH-