I don't find that's true at all. I've discovered quite a few genres this way that I might not have ever bothered to check out if I had to go buy an album first

I don't find that's true at all. I've discovered quite a few genres this way that I might not have ever bothered to check out if I had to go buy an album first (after all you want to be pretty sure you are going to like it before you part with your money).