You could, but even though I have a Dish account, I still get all my local channels over the air via my old Braund Skyliner. Dish's Little Rock channels are not HD yet but the assured me that they will be very soon, three years ago
When you travel, with sat you would have no ability to pickup local channels at all without an antenna of some kind. I have seen over-the-air add ons, so that is an option, but I can't believe that they would match the performance of a real antenna. More like one of those little things designed to set on top of your (or mom and dad's) TV.
Another consideration is your radio. In my Excella the Skyliner is also the radio antenna. There is a splitter in the wall where I connect to the TV that sends the radio signal out through the wall, out of site. It is part of the 12v
outlet/antenna outlet combo on the wall. Keep this under consideration too.
Let us know what you decide and how it works.