As the market for DRM is slowly maturing into a digital economy, it's interresting to think about how it's going to evolve. Namely what will happen to the content you paid (for a premium price given the real cost of the medium) after you don't want it anymore ?
So far you could sell your old vynils, CDs or DVDs to a second hand shop. And that created a real economy where people would purchase something they would keep for a few months and then get rid of it. But I think this possibility might soon become the past.
Consider the Managed Copy system introduced in future DRMs or the interroperability law in France. It allows you to go from one DRM format to another. But it's just a copy, the original is still intact. So if you sell the copy, you still have the original. You become a distributor and not a second hand seller, especially since you have the digital ability to make thousands of copies to sell. I don't think any content creator, major label or studio will ever let you do that.
And it's too bad, because given the digital possibility one could buy a DRMed movie (as in ownership, not renting) watch it, and then sell it for (almost) the same price. It would be fair to the buyer since the copy he would buy would be like brand new. Then this buyer could watch it and sell it after for (almost) the same price. etc. And if you put a website in the middle that acts as the middle man to find buyers/sellers for a content, it can be instantaneous. That means, the content you buy would be just as valuable as the price you paid, minus the price you resell it. It could be 0 in some case.
It could even make you earn money if the content is in high demand and there's no offer to sell it (the rule of offer vs demand). As in the analold world some content could be produced at a limited amount of items (DRMed copies) and the collectors would rush to buy one and maybe sell it for twice the price or even more. They could also sell a rare copy 10 years later for an expensive price (if all other copies have been destroyed).
Too bad the current DRMs won't let you do that...