The new text book thing isn't a requirement — but (a) professors get copies of the new books for free and (b) the publishers make just enough changes between ed

The new text book thing isn't a requirement — but (a) professors get copies of the new books for free and (b) the publishers make just enough changes between editions to make it hard to use old versions (different question, vocab words, etc.), so that teachers prefer all students to have the same version ... and this is only an option for the new books. Text books are somewhat irrelevant however — the Court upholding the first sale doctrine is fantastic, and hopefully will open the doors for lots more exporting / importing.