Sadly, it reminds me of the calls to boycott Disney/EA/Google/Amazon and others I'm probably forgetting. They're so big and ubiquitous that avoiding them is akin to quitting a given market.
Last year, Kellogg went on strike. Boycotts were called for, but trying to avoid all the various subsidiaries and such to honor the strike meant a lot of research into what brands were owned by them. Any similar boycott would be the same or more work. I'm not saying it's not doable, but the fact that you're going to have to convince collectors of dozens of unrelated brands to care is a Herculean task.