Sounds like a guilty conscious to me. Tell me you called ATT and told them that you are tethering with out paying them and its wrong for them to charge for it. If you cant do that, then your stealing because you know its wrong.
I have called AT&T every time my signal has been so crappy I haven't been able to make phone calls. I've also called them every time 3G has been rendered unusable for some reason or another.
I'm still waiting for them to credit my account.
I switched to AT&T from Verizon when the original iPhone came out. They've been stealing from me for years, and believe me, they don't care.
Why should we?
And by the way, I'm not jailbroken. But if I was, I wouldn't feel bad about using the UNLIMITED data I pay for however I want.