Yes, licensing. Unfortunately it is perfectly normal to see different music, apps*, films, TV shows and books available in stores aimed at different geographies. Not something that is specific to Apple either.
Typically the non US versions of the App Store carry much less content as well.
* yes, apps too. For some reason for example Microsoft at some point decided to pull their Bing app from the iOS app store outside of the US.
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Remind me to change my signature to something more interesting someday