This will change when people like Shaq and Bret Favre are charged more for insurance because their BMIs are in the overweight/obese range. And what about women athletes? Anyone who carries more muscle than fat will probably have a higher BMI because muscle, square inch for square inch, weighs more than fat. Anyone who has started working out and not changed their diet can tell you that they lost clothing sizes but their weight did not get lower and might have gotten higher (they lost fat and gained muscle). Been there done that myself (175 lbs in high school, not very fit, wore a size 18, 2 years later, 175 lbs, sorta kinda fit and a size 14).
Basing insurance rates on BMI alone is not a wise decision as it penalizes healthy fat people as well as the unhealthy. And fat is not as changeable as people would like to think. If I'm going to be penalized by my employer on my insurance coverage, it should be because I'm sick all the time and I use my insurance all the time, not because I'm fat, healthy, and don't have a reason to see the doctor all the time.