I imagine you'll find that people of certain lifestyles tend to cluster together a bit, with those with more active lifestyles and healthy diets likely to have their friends and family be of active lifestyles and healthy diets, and in turn less likely to be in need of such drugs. Lifestyle changes are difficult to implement by nature.
Although, the term "processed food" is awful as it covers so many unrelated things. The problem is ultra-addictive, ultra-high glycemic index foods consumed in large amounts partly due to their addictive qualities - a quality some processed foods have.
For reference, Danish sausage sandwich toppings are highly processed foods, but it won't drive anyone to obesity or diabetes. Elevated blood pressure, perhaps. Junk takeaway, candy and sugary cereals on the other hand...
Nothing to do with "processed foods" in general, despite a good portion of the affected foods being under that label. It's simply a matter of malicious companies combined with unknowing, unempowered consumers.
By trying to single out something as massively generic as "processed foods", you're just making it easy for companies to avoid the problem: Using and manipulating official definitions to be removed from it as a "solution", justifying the whole thing in the basis of numerous good things being in the same category, drawing attention to other foods in the same category that are more commonly associated with the term despite theirs being way worse, etc.
If you want to fix the problem, you need to attack the problem. That is not processing - it is addiction and glycemic value. Going for the underlying attributes means you cannot redefine your way out of it, and gives consumers a better chance to learn what to actually avoid.