Don't know for certain about the Phoenix area, but there are cable companies that will not install cable TV for a park, or if they do install it, they view each drop as a separate service and charge accordingly. That can make providing cable very, very expensive for a park, if each site is charged say, $40.00 a month. Have 100 sites, that is $48,000 per year. Pretty hefty. Also, the Phoenix Metro area has a lot of over the air channels available, plus many RVers have satellite systems. Maybe it just isn't a very high demand item. As for back-in sites, they tend to offer more privacy at the cost of easy entry and exit. Many seasonal parks do not have pull-thrus. It isn't a big issue if you only have to back in once every few months.
We stayed there last winter and did not need cable. The antenna worked just fine and had plenty of HD channels to choose from. As far as back-in sites, they are mostly just that. The place is loaded with old parks that have mostly park models and they sandwich RV's in where park models have not been placed yet. There are nicer and newer parks east of Phoenix in Apache Junction and beyond. Those have more pull through sites. Most of the ones closer to Phoenix are 20-40 years old and were not designed for todays bigger rigs. Be sure to check out the park you choose on Google Earth before you decide.