It’s a common choice for adding noise to snitch lines (e.g. a webpage or email address for reporting that you think your neighbor is an immigrant or that your boss hasn’t fired your black colleague yet).
Lots of folks spam those channels, and the bee movie script is a meme text to spam it with.
Not sure if I’m misunderstanding you here… But the number from this post is for the stupid military parade in DC with the tanks, not the no kings protests. I’ve seen claims that there were over 6 million attendees for those.