If I was running AC I would much sooner spring for a small generator to handle the load than carrying 500lbs of batteries. The honda 2000W units are relatively inexpensive, whisper quiet (the AC unit will make far more noise than the generator), and lightweight. The only time I'd consider carrying the battery capacity and inverter wattage necessary to run AC is if I was doing lots of camping in close proximity to others who might find my generator offensive.
Valid point.