I used to feel the same, about movies and books - have a ton of both and constantly acquiring more. I used to say exactly the same thing, even that I like my collection to take up space & the more the better! Although when reaching a certain point, it begins to feel like I'm some kind of hoarder and start to wonder why I really need a physical copy of something that I'm not even likely to pick up more than once every few years.
I've still got multiple bookshelves full of books and DVDs, but I've started to sell off stuff that isn't favorites, and have stopped spending money on anything that isn't really worth collecting. If its a favorite film, or a really nice release like Explosive DRAH, then I still like to have the physical copy. But if its just an average, cheap release, common film, or something that doesn't warrant highest HD quality, I'd rather just have a digital copy.
Plus there are all kinds of advantages to digital mediums that you don't get from physical. I can interchange audio tracks on films, with books I can make notes all over them and go directly to those notes, copy and paste the needed text without having to type it in, etc...
Same with music. Any more I just buy physical albums that have good artwork or are very special albums. The bulk, I just get digital.