For me it is more about ME being happy with the way I look. At one time I had put on 16-20 pounds, and I wasn't happy. My clothes didn't fit and I didn't like the way I looked in my knickers. Mister, he couldn't have cared less.However I wanted to go into middle age fit and in shape, so I lost the weight and have been exercising regularly ever since. At first it was a chore but now it's fun, and Mister and I both enjoy the benefits. It's okay if I never look like Anna Kournikova, but I would like to be as fit as I personally can be. Which means that I might always have a round belly, even if there's a potential 6-pack underneath. But hey, I guess that's all right for belly dancing, huh? ;-)
One thing I think young people may not recognize is that most models, and of course athletes, have to WORK at looking like they do.