I don't think that anyone would say the primary purpose of a bookseller or a garage sale is to provide items to dealers/resellers looking solely for the most valuable items. And many would agree that those sorts of vultures reduce the enjoyability of both bookstores and garage sales. So imho, if there is a way to limit that sort of patron, eg via banning barcode scanners, so much the better.
Reminds me of the problems with resellers attending garage sales: it takes all pleasure out of leisurely perusing sales, and perhaps finding something you'll take home and actually give new life to, to fight shoulder-to-shoulder with dealers looking for items they can turn a profit on. And from the one garage sale I have held, I can tell you dealers drive hard bargains in the most unpleasant way to get you to sell to them at ridiculous, disrespectfully low prices. They are selfish leeches and shouldn't be allowed at garage sales either.
It's peeved them ever since www and graphical browsers came along that they weren't controlling or making money off all this human interaction. The technology (and their lack of understanding of it) cut government out of the loop from the start.
I really think the Wachowski brothers had it right with The Matrix imagery. Our government sees us as nothing more than perpetual energy sources for its own sustanence and immortality. So I'm all for limiting their power while we still can.