They are stricter than Spotify with regional licenses unfortunately. I listen to a lot of Japanese artists that are on Spotify but not on GPM in Europe (but are there in Japan), I simply imported their albums and ripped them and uploaded them on the service and now they behave exactly the same. Not ideal, but still. For like 90% of the rest of the library (anecdotal experience at least) it's the same as Spotify, which is pretty great.
DISCLAIMER: I work at Google, but I've been using GPM long before that. These are my opinions and not those of my employer, yadda yadda.