Are pharma companies actually advertising these things, or is it a bunch of malicious actors that don't officially represent the pharma companies going out there and blindly tell people to go get this shit? Also, I wouldn't be surprised if the legal immunity granted to pharma companies for these shots extends to hiding potential negative side effects.

Isn't that only if the company itself is advertising it? i.e. if it's a govt department they don't have to.

Not just side effects. All REPORTED side effects.