I see the downvotes, but I still don't see how some guy self-publishing and printing his own book at Kinkos is proof for a conspiracy in which publishers collud

I see the downvotes, but I still don't see how some guy self-publishing and printing his own book at Kinkos is proof for a conspiracy in which publishers collude with professors to force students to buy books from that publisher. If anything, it's an example for the exact opposite.