Can you sign up for Aereo, give them an address in the market you want to watch, and then receive out-of-market locals? I know their terms don't allow that, but theoretically, is it possible?
From what I understand, Aereo looks at the IP of the ISP you are using and if it is not within the DMA it will not allow you to log in. At least that's the story.
Aereo to my knowledge does use your actual location though I'm not sure they need to. They do need your credit card address to match your stated City address however. With streaming from the all the carriers quite common now, and all the streaming devices, I don't think there is an issue streaming your locals to wherever you are.
It is very easy to make your IP match where you say you are.