Just take the signs off and throw them away if you can.

If they are on the outside of a door hit it on the way in if you see a trashcan near by. If they are on the inside or you don't see a trashcan then grab it on the way out.

If the sheep don't see signs to reinforce the fear narrative and they become less afraid.

I've been doing this for the last month and most places haven't replaced them.

It's a simple act of rebellion against tyranny.

And yes, stealing is illegal but so was the American Revolution. Grow a pair and fight.