I don’t think downloading the titles is enough. While you and me may have enough space in a spare HDD for every movie we ever purchased, my parents certainly don’t have enough space on their iPads; and even then they wouldn’t be able to watch them in their living rooms. These digital storefronts should be forced to serve the movies they sell for streaming indefinitely so people like my parents have a way to watch the content they paid for with the same simplicity they had when they bought them