stutz, I don't know what you're talking about with marketing.

This diet to my knowledge has never been marketed by any food company or corporation.  It's literally been a word-of-mouth, word-of-blog and published books movement.  Heck I would think the big food makers that churn out boxed processed foods would be against it.  As stated, the core is simply eat whole foods, that's it.  Some say legumes are okay some don't, they all agree on the basics though, stop eating processed breaded/sugar'd foods.  Period.

You also mentioned these people are fat not from eating processed foods but from eating a lot of it.  I'd disagree.  Every really large person I've personally known (mostly family) eats....everything.  Whole foods, processed foods, everything.  Taking out that processed food but still letting them eat whole foods would most likely help, do it for years and they'd probably lengthen their lifespan.  It's pretty simple, processed foods take longer for your brain to tell you you're full, so you keep eating.  It's really not their fault no matter how much fat-shaming we want to do.  They're eating until they're full and the food companies realize the more sugars and addictive additives they can put in a food the more boxes you'll buy, the larger your stomach expands, the more you can eat, it's just genius really.  Again fat-shaming them doesn't help, that's clear, so telling them to just eat less of that processed food has gone no where.

I'm fine with the diet, and movement, only issue I have with the hardcore ones is legumes.   I think they're fine, so do studies in South America on their high-legume diet.

You also mentioned potatoes, potatoes are fine, not during Whole 30 but non-fried, red/new potatoes are fine.  Sweet potatoes (roots) are like the food of choice for them.  yes, I'm pretty sure cave men/women ate roots like sweet potatoes.

Simply telling people who are fat, "stop being a dumbass" won't do anything.  It's like telling a smoker "dumbass just stop smoking."  Nothing with addictions is that easy, if it was there probably wouldn't be any smokers, or any fat people.  Do you think they enjoy being overweight?  Stopping smoking, alcohol, heroin, whatever takes processes and work, steps, etc.  This diet is similar, start slowly, cut out, this, then that, see what results you get, see what caused you problems that you didn't even realize.