Did you think Blockbuster or any other rental store could buy a copy from Walmart and rent it out?

YES! That's how it fucking worked! For the exact same reason libraries can just buy a book, and then lend it out, because they fucking own it. That's what the money was for!

Rental chains only developed contractual relationships with movie studios because it's otherwise kind of difficult to buy five thousand copies of one tape. Studios sued, and lost, and came back with a truce.

The first sale doctrine is over a century old. Every medium has tried insisting it's special, and been slapped down as just another product. Software has been long awaiting that slap. Their excuses aren't anything new. Your rights have not changed.