You can make a patched torrent client that never uploads any pieces to peers. It'd definitely be within Meta's capability to do so. The real problem is that unlike typical torrenting lawusits, they weren't caught red-handed in the act, and would therefore be hard to go after them. This might seem unfair, but it's not any different than you openly posting on Reddit that you torrent, but it'd be tough for rights holders to go after you even with such admission.