In the weight gain dilemma? Well... I live in the US.. which is notorious for its 'weight problem'. More specifically I live in Texas... which is known for having a big 'weight problem.' And then I live in Dallas... which has an 'obesity problem.'
I see people engorging themselves everyday. Sharing in a meal is used in celebration, closing a deal (in the business field), a way to properly greet guests/relatives, minor entertainment, and a way to satisfy curiosity (oh... I haven't went there before). The shear number of restaurants here is staggering... and the vast majority are not health-conscious eating places.
So I know... it makes the obese feel 'bad'... but I have to side with the idea that the majority are overweight because they simply do not realize that the good food they eat far exceeds their energy requirements. Many health problems here in Dallas can be attributed to the weight problem --- not the health problem causing the weight gain.
True... you'll have those who are overweight due to genetic disposition, medicinal side effects, and mental illnesses causing irregular eating habits --- but that's just a minority. The majority are willingly putting either excess foods into their bellies or food with excess energy potential that exceeds their requirements into their bellies.
They don't have to necessarily exercise to be 'fit'... but eating within the range in which your body's metabolism can keep up couldn't hurt.
"The weakest soul, knowing its own weakness, and believing this truth that strength can only be developed by effort and practice, will, thus believing, at once begin to exert itself, and, adding effort to effort, patience to patience, and strength to strength, will never cease to develop, and will at last grow divinely strong."
- James Allen