I've always argued that DRM stands for digital
restrictions management not digital
rights management as the publishers/record labels/studios would have us believe. They provide precious few rights with the "purchase" of their products, but plenty of restrictions as to how you can use digital content.
If I buy a (print) book, CD/cassette/album, or a DVD/blu-ray and don't like it, or simply decide I don't want it any longer for any or all of a variety of reasons, I can gift it, sell it at a yard sale, sell/trade it at a used store and no laws have been broken. Attempt to do that with any digital media and you are committing a crime, even if you relinquish the originals and all the licensing to that media. Add in the fact that they can (and have) stop you from enjoying content you have full legal right to, at the whim of the company. I understand their fear of piracy. I also understand that as long as I'm treated like a pirate without any evidence, there's very little digital content I'll ever purchase. I further understand that the DRM security they build is only paid for by legitimate purchasers, is incredibly expensive, and is typically broken within days, even hours, of it's implementation making it worthless.
Rent or borrow? Yes. Purchase? No. Just no. At least, not very often.
I do so love Cory Doctorow. He's actually removed all his works from Audible because Audible will not sell content that is not DRM protected, no matter the author's wishes. It's because DRM is not there, despite protestations from the labels/publishers/studios, to protect the content creators, but to protect the content
providers profit margins and allow them to keep us penned up in their particular box.