What you’re describing is data hoarding. I pirate a ton too, but you know what I do with a movie or TV show after I’ve watched it? I delete it. Poof, gone. But it’s still in the most important dataset I have. My memory. To help with the metadata of my own memory, I write down a list of the films I’ve seen. I only keep the movies I really love and want to rewatch (Robocop). That TV show I just finished that was great…
I don't pirate, I pay for content, but I like to own a digital copy of music content. So I buy MP3s rather than subscribe to a service. It's probably strange-- and maybe dumb-- but I feel like in the long run I never know what will happen to a service in terms of how it may change in price or quality. If I own a CD or an MP3, I know I have what I want. It may not be rational. I know some people think I am crazy.
Listening "offline" by installing a shitty app is a severe service problem. It punishes me as a customer and doesn't stop any piracy anyway.
Files are just so much more flexible than an app. From my favorite artists I usually still buy CD since there are almost no alternatives. Of course I would prefer a digital download. Some offer it and that is much appreciated.