Quite an assumption you have there. Industrial food is cheap and crowds out normal food. Some areas are basically food deserts. A significant portion of the population also has health issues that complicate maintaining a healthy weight.
So called "food deserts" are a bit of a chicken and egg problem. Are the restaurants in your area a reflection of the eating habits of the people in that area, or a grand conspiracy to keep us unhealthy? I tend towards the former.
I am also skeptical that even in "food deserts" an enterprising individual can't acquire rice and beans.
for example, if they have recently made the decision to stop smoking cigarettes, thereby making a positive change in their lifestyle and health, this shows strength of character. it also demonstrates their ability to question past poor decisions rather than give in to the sunk cost fallacy, and then take steps to correct them. and of course, it also tends to make you put on weight [0] ... although not much more that 10 lb or 5 kg it seems, so interviewer beware, i guess ;)
0. <https://medlineplus.gov/ency/patientinstructions/000811.htm>
No, it doesn't. Not being fit merely tells you that they might have lifestyle choices different from your own.
Or they might be female with PCOS. Or they might have a disease that causes fatigue or pain when they exercise. Heck, that might be the very reason for their desk job. Or a history of food insecurity and really need the insurance the job provides to be able to afford therapy, if they are even to that point. Heck, they might just not be knowledgeable enough to separate bad health advice from good health advice and despite trying things out, feel stuck. It isn't like I learned how to care for my body in school, after all. Health class focused on STDs and parts of the body while physical education classes were more focused on sports, rules, and being a good teammate.
The reality is that being overweight only tells you that they are overweight.