I blame the online sellers more than the scummy buyers.
sonys site is the only one to stop the bots!
Yeah we have original (limited edition) products on sale (we make them, it's not scalping of course) but we put them up for lottery and then go through the lottery and (partly manually) review and remove any entries that look suspect.
Specifically we know exactly when our lottery is live so we can see which entries are far too fast to have been done by humans, and we just reject all of them, close their accounts and also block the IP address if they are stupid enough not to use a VPN. A few of the people in our team do a mock order before we put the products live to see how long it takes us to order (adding a few seconds to account for the server likely being slow to respond when it is live) and then we have a handle on roughly how long after products are live that a customer ought to be able to realistically finish placing an order/an entry.
We have it in our terms of service that using bots to game the system is against the terms and
will result in account closure, as well as efforts by us to close any future accounts they attempt to open (we put their names, address and other info on a blacklist).
Our site is relatively small and we're not exactly on the scale of Amazon, Walmart, Best Buy etc, but I don't really think it's that hard to combat this stuff if they actually made an effort.