I don't really blame Winegard...not to get too technical, but there are two types of "receivers" needed at the end of the dish - a KU band and a KA band (think of it kind of like AM/FM). DirecTV decided to transmit Standard and HiDef on two different bands - while Dish uses the same band.
It makes the most sense for Winegard to sell the auto sat systems that can receive the most channels - since all the hi-def are also broadcast on standard def.
In order to get hi-def on Direct - you would need a manual sat dish that has both KA/KU and receives multiple satellites. Problem there is they are very difficult to align - especially trying on a tripod in a campground.
For the providers it really boils down to finding the system that they can pump the most channels into given the spectrum and satellites positions they have been given. Unfortunately the RV community is such a small percentage of their total business - they are not able to do more for us....