...Your MAC address is likely recorded in all of those places via the router. They could trace back the infringement straight to your computer's network adapter.

A better way would be to get a proper VPN service. TorrentFreak just released their updated list recently. That will help to mask your router's MAC and thus actually providing some anonymity. Mind you this assumes you're using Windows, which has some lovely backdoors that the NSA is using. Not that anyone, including myself, actually cares. So take anonymity with a grain of salt. Also don't forget about super and zombie cookies.