So to summarize, I use it cause it's a fast way to sample new music. Some people also use it cause it's easy and legal.
Sir, you need to get on Google Music. I checked out Spotify, I am not sure what they are doing that could better what Google offers (which seems to be their same package plus more).
As someone with a huge ass collection myself, I swear to christ I have no clue where I had been without the ability to edit and tag and organize and just listen to my music, without Google.
Sample I just took for you for this thread of my favorite thing in the world, their 'instant mix'
I took that fist Intronaut track, right cilcked, and bam, an actual well working Instant mix. I throw so many curveballs at this thing, and if I look at the playlists by name, it sometimes doesn't make sense, but if I just listen to any instant mix, it tends to be amazing and I seem to have been walking away so much with new tracks from artists I knew, but maybe did not have full chances to listen to their albums and etc.
Sorry this sounds like a fucking Google ad lol, but I love music more than my life, so if I hear someone has a mass collection, then you are hindering yourself by not giving this a shot (if you can get in the beta).