2) I think I've flash-learned a lot about the process now (of which I knew little before). I'm really interested in disruptive uses of digital social systems, so taking advantage of online vendors might be something I'll actually look into for a future research project.
3) Random thought: Given the increase in algorithms that weigh prices against other sellers (and the obvious examples I linked to in the piece) I wonder what the potential is for mom-and-pop businesses to employ their own algorithms... or at least what the conflicts are when you have small businesses with different levels of technical skills and access to those sorts of advantages. Is that a new business competency that's necessary if you're a small business looking to work within these systems?
This feels to me that this is probably news to you, which is why I'm making it explicit. Given this background, talking about their algorithms sounds silly: they're not sophisticated Internet businesses with Stanford CS majors optimizing for ROi, they're closer to flea market merchants and their accounting controls would have gotten them dismissed for incompetence by any bank in Renaissance Italy.
That said, I get to deal with the occasional "OK, now that our event is over I don't need this anymore, how do I get a refund" email. I eat all the costs on those and don't argue because there is no profit in arguing, but one can understand if I don't have those folks in my Favorite Customers Hall of Fame. You bought a book from a mom-and-pop business, got exactly what you were promised, and then -- because it was convenient -- reversed the transaction and stuck them with all costs. You're a textbook pathological customer. Do you understand why people might not want to work with you?
[Edit: Oh, the economics of the "dispose of it how you want" are fairly straightforward. It simply isn't worth restocking/shipping/admin overhead to take the item back. We had a similar canned line at the office supply store I worked at: if you complained your paper was "Made out of trees!!!" and that prevented you from using it, I would tell you to "Donate it to a local charity or otherwise dispose of it in any way convenient to you." Same thing with BCC disks: they're cheaper to print than to ship and if you hypothetically sent one back to the factory they would just destroy it and charge me for wasting their time.]