No one is required to continue with their past buying habits once their mind has changed.
The word 'mob' implies unregulated violence, usually based on emotion and not reason. And the vast majority protesting racism appear to be peaceful and thoughtful.
That is correct but it’s not relevant to the specific scenario brought up here, which is if you’re on the wrong side of a group that is not peaceful and thoughtful. Those who are in such a position often receive death threats. The outrage of the internet that has latched on to something it wants to believe can lead to remarkably mob-like behavior, though with less physical violence usually.
Seeing as going to war and accepting civilian casualties has only been acceptable for the entirety of human history up to and including the present, I’m not so sure.