So I have the right to flip off your mother at the grocery store and call her bad names. Technically its
not illegal. She shouldnt have taken the last bottle of aftershave. Don't be pissed off.
Just because something isn't 'not allowed', doesn't mean its right.
Are you serious? That comparison makes no sense what so ever. These are "professional athletes" who are....wait for it....paid to perform. If their performance doesn't please the fans, regardless of right or wrong, they have the right to boo.
Now about you flipping off my mother for picking up the last bottle of aftershave....that would be your fault for not arriving sooner. It would also most likely put you in a world of pain because I wouldn't do it to a elderly lady and I won't stand for it happening to my mother.