Netflix is considered the main driver behind this DRM madness. In the context of Netflix, an often voiced reason for DRM is the fact that it rents movies, rather than sells them. Besides DRM being completely ineffective to prevent piracy, the concept of rentals itself doesn't make any sense for digital goods. The core logic behind a rental (for physical goods) is reusability. Physical goods have a fixed cost of produ…
So that you can segment the buyers into two: Those who want to see a movie only once and those who want to see it more than once. This way, you can double charge the second segment and use those funds to reduce the price for the first segment. Classic market segmentation.
As long as there are customers of both kind, rentals (even for digital goods) will make sense.