My HR44 is "mobile" while on the road but not so "mobile" at home. :? But my MH dish is portable while the S&B one is not. I suppose that DTV is correct in that DNS is "mobile"
However, over the years DTV does seem to have more training related to "mobile". In my cas I'm a "valuable customer" and get what I want changing the service address and I don't abuse it by changing every day.
Basically DNS (LA or NY locals) and your own mobile dish is "mobile". DTV does seem to handling us RVers better.