The HGTV show has to deal with the big "wow" factor for the sake of the general viewing audience, which is why you see the big expensive rigs predominantly featured over affordable, real-world RVs. Experienced RVers would likely want a different product mix for the show, of course, but given the audience that likely numbers in the millions for HGTV, that's an awful lot of general non-RVer viewers. The formula seems to do well for HGTV since they keep repeating it each year.
As co-host of an upcoming new cable TV RV show, Rollin' On TV, I can assure you we'll be covering the entire range of products used by real-world RV enthusiasts. And truck campers are definitely on our radar because those are some of the most fun RVs we use! But keep an eye out for the show, and we'll try and deliver a package that's entertaining and useful at the same time.