I don't think I've ever double-dipped. To me, it never made much sense because I'm a collector. Why do I need another copy? I already own a copy. And plus, I'm the type of person that wants to play games the way they were when they launched. I don't want to play a modern re-visioning of them. So there was just never a need for me.
There's always a need, example I could not stand the bad aliasing up to the ps4 era, therefore I will quickly update or repurchase games on the newer consoles just to have a sharper cleaner picture, why wouldn't I? That's like someone having an iphone 4 and never ever upgrading it. Why would I limit myself. Some repurchases are actually very cheap, GTA5 was like 10 dollars for the full game and looks miles better than on the ps3. Another example, shadow of colossus, just try playing it now on a 75inch screen on a ps2, it will look totally horrible compared to the ps4 remake. I would never even think twice about getting the upgraded version. Games are not movies or music, video game graphics actually improve very quickly in just a few years. I cant even manage to play ps3 let alone going even further back. I tried the first infamous on ps3 recently and I just couldn't do it, and even tough all ps3 games are free, I still don't want it.