The funny part is, I don't eat 'Paleo' or 'LCHF'. Even on a low-carb day I probably run about 125g of carbs (easily twice that on others), which is well above any sort of ketogenic diet. I also eat rice, some dairy, corn, etc., so that disqualifies me from 'Paleo'.
Having said that, I have a hard time throwing stones at someone who wants to eat a diet of wild caught fish, naturally raised livestock, nuts, seeds, fresh fruit and colorful vegetables. The big sticking point seems to be 'healthy whole grains'. Plain and simple, this is not a necessary component of life. If you like to eat it, knock yourself out. If someone decides they don't want to eat it (for whatever reason) how about live and let live?