The fundamental difference in terms of economics between a physical thing (book, food, whatever) and a piece of digital information (bits, bytes, a text file of a book, a video file of a movie, a game) is that you can copy the digital information infinitely many times at no cost.
So then this DRM technology is introduced so that they can still base their business models on scarcity - if something is rare you can get a lot of money for it. This is done by having a "black box" computer program that only grants you certain types of access to the files/games and also enables the company certain types of privileges (e.g. upgrading or deleting it). [N.B. those old games that required the CD to play aren't considered DRM]
They could build a system that restricted certain actions (like copying the files to another computer or over the internet, or skipping adverts, for example) by technological rather than legal means while still doing everything just as the consumer wants.. but my view is that's not the end of it. There's still something I care about that's being threatened: freedom. If it becomes mandatory of have black boxes on your computer it'll be the end of computers being a tool we use, but instead we'll be at the mercy of computers.
My ideal would be that people distribute freedom-respecting software and put legal restrictions on it (like make it illegal to distribute it over the internet). [analogy warning] DRM to me seems like doing a retina scan on anyone that wants to drive a car, and confirming it with some third party organisation before letting the engine go. My biggest worry is that instead of putting legal restrictions on the files they distribute they start to put legal restrictions on the technology we use. Being able to use your computer freely for things like writing your own programs or running an operating system that you're able to check the source code of could become outlawed.