It's all about how you feel. If you can't get up a flight of stairs without choking or if you'd rather take the bus when you can walk, that's when the bells should start ringing.

There's nothing wrong with having a bit of a belly and feeling good about yourself, I do it all the time, I know I'm fucking fabulous and I know that my BMI is basically somewhere in the category of obese.
I take pole dance classes twice a week and do cardio & weight lifting at home, I walk when I can and I ride my bike everywhere. I eat a lot of veggies and fruit, especially in the summer.
I feel really good and my weight doesn't have anything to do with it.

There's a difference between being a bit bigger and being a total fat lazy ass.
What's wrong with this world is that it's always about looks and less about health.
We shouldn't promote muscles and a tiny waist, but rather being healthy, eating good healthy food, stop McDonalds and all that crap and actually have good food available for people, even the lazy ones.