I'll assume this was a serious question. While recording a show yourself and downloading it both produce the same outcome, copyright law cares about the path that bits take. Even if the TV networks are distributing something for free, it isn't legal for you to redistribute it for free without their permission.
An interesting post I read about this a while back:
http://ansuz.sooke.bc.ca/lawpoli/colour/2004061001.php
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.
How is bit-torrenting TV episodes illegal?
They are broadcast into my house for free, so why would it matter if I record them, or if Some Guy On The Internet records them for me? (I never watch TV un-timeshifted, so I don't see ads either way.)