Boas and woma pythons do fine without heat pits. It's just an addition to the majority of pythons. Besides, who said they still don't detect infrared? Maybe those pits were just holes in the scales that exposed sensitive skin, just now there isn't scales to have said holes in.
As with all animals in the pet trade, they can have mutations/deformities and still survive as uniqueness is simply a desired trait. Humanity has essentially formed its own game of survival of the fittest, except its survival of the prettiest. As long as they are fed safe foods and retain belly scales for mobility, they're okay with me. I just wonder if their eyes are ever irritated- that would suck to have irritated eyes and not be able to blink. I would also keep them slightly more humid and use softer, dust-free substrate. Although I would love to just settle for bald ball pythons.