For me, downloading has a few uses.
1. A way to test a film or music. If I like it, I'll buy it. Downloading has not become a alternative to buying for me.(youtube has also become a great way to "sample" music)
2. My impatience. If I like something I will view a downloaded version to hold me over until the official release comes along. For example Dredd came and left before I had a chance to see it a second time in theaters. I watched a downloaded version until the bluray release.