> It is legal to bring 90 friends to your house and watch the movie together.

Technically it is not legal to do this. At that point, you're putting on a "public performance", and they may indeed sue you.

Where is the line at which "having a few friends over to watch the game" a public performance? It's up to the NFL's lawyers and the corrupt judges that decades of copyright cartel lobbyists have schmoozed.