If they don’t control most of the nodes in-between they can control all the exit nodes they want. If you connect though 3 Tor nodes, as soon as one of them is not controlled by them they likely can’t identify you.

That’s not to say that they don’t control most of the nodes, and your traffic likely goes through NSA nodes exclusively

“Czesc, I am Mister Anonymous. I would like to buy this Book. Please send it to Jan Pawel at this address, dziekuje.”

I am not sure what he’s hinting at. Just using Tor doesn’t bear any legal risks. Hosting an exit node is different, as depending on the country you might get into serious trouble if certain traffic goes through it.