Spotify has disabled the purchasing of music tracks in the UK. Users attempting to download a new track in the official app will see a notice that Spotify is "currently not supporting new download purchases." Clicking on the notice takes you to an FAQ that states that users with download tokens will still be able to use them to get tracks. Users that have a valid gift card will also be unaffected.
Given that Spotify states that it's "currently not" supporting the feature, which has never been available in the US, it's not sure that this is a permanent move. We've reached out to the company for clarification on why it has disabled its download store, and will update you when we hear back.
Update: Spotify has also disabled purchasing in other European countries. Users in France, Spain, Germany, Sweden, Norway, and Switzerland are seeing the same message when attempting to download tracks.
Update: Spotify has provided us with a statement on the matter: "We recently updated Spotify to further simplify the service and pave the way for new features announced at the end of last year. In-app purchases aren't part of this update but we're not ruling out their return. Credits/gift cards already purchased are still redeemable."