You saw/heard/etc. something you consider abhorrent ( e.g. shout racial slurs at a teenage footballer, sexually assaulted someone, etc.). You can't believe such people exist, and can't even remotely relate to them. You're pissed, terrified that those people exist and they seem to suffer no consequences for their actions. So what do you do? Good old boycotts.

I think that the whole thing ( "cancel culture" ) is overblown, on both sides of it. There are absolutely terrible people who should just shut up and be deservedly ostracized for their abhorrent actions, but it sometimes goes too far for too little; and on the other hand people who scream "free speech" when a bigot gets fired for shouting racial slurs aren't helping anyone and make themselves look sympathetic to said bigot.