Epic seems to have bought it for the relationships Bandcamp has within the music community -- they see Fortnite as a multiverse, and they've already hosted a couple of concerts. The Bandcamp and Harmonix acquisitions seem to be feeding into that, so hopefully they won't ruin the existing products in the process.
I suspect the real answer is even more cynical: Epic bought Bandcamp to make a point in their fight with Google (and Apple) over in-app billing.
I feel like that'd be the least bad reason to buy it.
Epic's only interest in it appears to be to pad out their litigation. I expect they'll lose interest in it if they can bribe and sue their way into making it easier to get gambling in the hands of pre-teens.
I am sure they will shorten tracks to samples without logins or try a subscription model. I am just waiting for the platform to go sour. I recently downloaded Soulseek again after 20 years. It feels like we’ve gone full circle. I like Apple Music but I want to have copies of my music on disk.