I don't think it's a waste at all! I grew up having to buy a physical copy of everything, video games, movies, music, everything. Although times have changed quite a bit, in a world were any of those things can be digitally owned, there's still something nice about having a physical copy, it's there, it's yours, it looks nice on a shelf. I buy digitally as well, of course, but movies or games that I really am I fan or enjoyed I'll definitively buy the Blu-ray!
I rather rent a movie cause if I don't like it than it isn't much of a loss but if I buy it it is a lost especially since dvds are starting to get expensive
Personally i watch all movies online for free because it is a lot easier faster than buying one in store or on the internet, and also faster than renting. Yes it is morally wrong but the day I stop watching them for free on the internet is the day I'll give up smoking! (Which wont happen anytime soon hopefully lol)
I only purchase dvds for the movies I really like. I'm very frugal and if its a movie I'm only going to watch once or twice then I will wait for it to show on television, rent it, or watch it online for free. The last dvd I purchased was I am legend.