I get the impression there's an attitude from the newer generation of tech workers--the ones that are more progressive and less libertarian--about their right to unionize. They were so interested in union politics and the reading about the glory days of unions that they overlooked their current situation. You don't sell a company to break up a union and lay off half the staff. Bandcamp wasn't a good fit any more, and…
I suspect Epic had plans for bandcamp, for various reasons they had a change of heart... and re-sold partially out of a combination of frustration and the shifting economy. This wouldn't be the first time a somewhat purpose-driven company had a post-acquisition fallout, and it won't be the last.