Ground Cheater plug or....

Maybe this isn't a good idea, but I thought I'd ask anyway.

I have what I believe to be a persistent ground loop hum from my amplifier. It's quiet, inaudible if music playing or unless you're standing next to the speaker, but knowing it's there is annoying.

I've heard suggestions to use a cheater plug to defeat the ground, but it seems counterintuitive to stick a 35cent plastic plug between expensive cables and power supplies. My question is, couldn't you accomplish the same thing by disconnecting the ground wire in the outlet, and still exact the benefits of better cables?

I'm sure the fire marshall would disapprove, but I'd like to hear what the hi-fi nuts have to say.

Cheers!