I'd even be happy if it was required to be covered for functional reasons. So many people have been denied jaw surgery coverage (myself included) for legitimate functional reasons simply due to the fact that their employer's health plan has a direct exclusion for jaw surgery. They then have to delay major life decisions (buying a home) due to needing to use savings/loans to pay for surgery.
I agree with you though and I see where you're coming from. Especially since people who've eaten themselves into morbid obesity can get covered for gastric bypass AND often skin removal surgery after (my heart still goes out to these people though, this comparison isn't meant as a criticism). However, people with legitimate jaw deformities cannot help it at all.