This is all riot control gear. US universities usually have their own police departments, so by extension they usually have their own riot control gear as well.
You wouldn’t use any of this stuff in war. It isn’t designed to kill people (although it can and will, especially if used improperly).
I think it varies a lot by the user. I think (hope) most people are just joking, but I’m sure we have a number of people who aren’t joking.
But also keep in mind we absolutely have propaganda bots and trolls here. They’re quite good at directing the hivemind, even without the assistance of complete loons.