This is a great way to prevent people from hearing your music... nobody wants to trust your "Album" app to not contain a virus.
Also, you can still listen to their music on soundcloud [1] if you don't want to review the code. It's open source after all, which can't be said for most demos...
[0] https://en.wikipedia.org/wiki/Demoscene -- Check this video for a neat example: https://www.youtube.com/watch?v=6AUpZNq2vSQ
I'd have thought the bigger obstacle to people hearing your music is that people tend to prefer to listen to music in their music player of choice, in their own playlists or on shuffle. Then again, maybe creative control over how the songs that compose the album are listened to is part of the app's raison d'etre.
That's not the concern here. How many applications do you have installed? Maybe 10-20 things for the average user. That's pushing it really now as most things are in browser.
Now given that, how many music albums do you own? 10, 20, 30? It's not uncommon to see people who have in the 100s (at least in college).
If you need to install something for every one of those albums that's a much harder space to audit then 1 music player.
It's not exactly as if good old-fashioned music CDs never installed rootkits on users' computers either.