You can live a completely sedentary lifestyle and lose or maintain weight through eating normal amounts of food. Exercise is not the problem, overeating consistently is.

For women, it's very common to consume sugary coffee flavored drinks and this behavior is glamorized on social media.

For men, the problem is worse.

In theory sure, but teenagers love sugary drinks and burgers too, sugar drinks exist all over the world too where obesity rates are significantly lower. While you can be slim while sitting all day doing nothing, being physically active is massively important for your health.

The fact that the particular area you live in determines so much of the probability a person would be obese suggests the location plays a huge part. While sugary drinks are marketed and popular everywhere.