I don’t use Bandcamp but have explored the possibility of making a Bandcamp plugin…
First off, their API is geared towards artists, labels and merch vendors instead of the consumer. This means it’s not possible to access Bandcamp resources through officially supported methods. Nor would it be possible to perform authentication and access stuff that is specific to your account, like purchases and followed artists.
It may be possible to write a plugin that scrapes publicly-available data from the Bandcamp website and play the low-quality MP3 tracks you can find there. But I would like to know if it is worth the effort of doing this?
Furthermore, if you don’t have a Bandcamp account, are there restrictions on what songs you can play or the number of times you can play anything?