Your problem is that you are being rational, and copyright law is anything but. I don't think there has been a definitive ruling on the matter but I think torrenting is illegal because you never own the show, you have a license to view it in one way and viewing it in another violates that license. For example, if I get the show in HD on my package and you don't, me giving you a copy means you have an experience that you would not otherwise have and therefore are violating the copyright.