Default [Q] Why Are Apps Country Specific?

Okay, so I'm not getting it.. Why do all these awesome music apps have to be so country specific..? I mean, people from other nations appreciate English music too, and are very capable of enjoying the benefits.. Why does USA get all the fun? I've got the apk of some apps (cause hey PlayStore is racist that way too) and now to find out it still doesn't work. Pandora, Play Music (Radio), Songza, a whole lotta other non music apps even.... What's with the apps not wanting to provide fun to the whole world? A genuine question.

Yeah, I've seen tons of guides and all for workarounds to getting those apps to work, but seriously, my question is WHY are they country specific in the first place?!?
Just looking for an answer, not a guide or tutorial to get them.