@WillyWollyWandy
Ok you asked..
I would never dream of commenting about someone’s weight. But I do inwardly judge people who are fat because for the fast majority of people, notwithstanding those with thyroid issues and other health conditions, there is no need to be fat. If you eat healthily and exercise, even only having a walk a day, you will not be fat.
So if a person is fat, I assume they’re lazy and eat junk food to excess. They may argue that they don’t, citing gym sessions etc. However if they accounted for every calorie that goes in, and that includes finishing the kids’ dinner, the hugely calorific takeaways and wine, it would easily outweigh the output. It isn’t rocket science.
But as I said, I’d never actually say this to a fat person, albeit I don’t really know any fat people.
I do know anecdotally that people struggle with their weight. But some willpower and discipline should fix the issue.
I also presume however, that for some larger people, there are mental issues at play which leads to comfort eating etc. No idea what the answer is. Counselling?
But how do you know if the fat person you are inwardly judging has medical issues or not? Unless you ask every fat stranger you see.
For the record, I'm 5ft 1 and a size 24. So far far more than overweight.
Could I "eat less and move more"? Of course. But there's far more to it than that.
I have mental and physical health issues. Some of which/the medication for which causes weight gain/makes losing weight harder. This includes mild agoraphobia meaning going out 'for a walk' takes a massive effort. Add to that the abuse I've had shouted at me when I am walking for exercise and it makes me want to give up.
I'm also unable to work (due to mh issues) and am still battling with the JC to be awarded LCWRA which will lift the benefit cap and mean I can actually afford to live. As it is I'm trying to feed 2 teens and myself on not very much money, so cheap filling carbs are the way to go. For me at least. They have a far better diet than me but I stretch the budget by going without.
I've also got an entire childhood of mixed messages around food too contend with. If I didn't finish all my dinner I'd be told "don't you know there are staving kids in Africa?" If I did finish it I'd be told I was greedy and that there were starving kids in Africa 
If i didn't eat dinner because I wasn't hungry I get told I needed to eat 'proper meals' and asked if I had an eating disorder. If I had dinner I'd get told i didn't have to eat just for the sake of it.
Even now, if I go out with family and don't want cake I get comments like "you are allowed cake you know." (No shit. I'm 37. I'll have cake if I want.) If i do have cake I get "hmmm.... are you sure you should have cake?"
Even as a teen, who danced 6 days per week in classes plus practiced in all my spare time I was a size 14. Which is "overweight" for my height.
But yeah. You go on 'inwardly judging' me.