What there is a lack of is compassionate, practical help. It's quite a bit like smoking; few people would argue that they didn't know they were smoking, the issue is whether they care about the negative health effects and how they can actually do something about it that sticks.
I used to be obese, so I completely agree that fat people usually are somewhat aware of how fat they are and of the health impacts. It's just hard to make them care, and they need help with going through a lifestyle change that they are going to make mistakes during.
[1]: http://www.abs.gov.au/ausstats/abs@.nsf/mediareleasesbyCatal...
For example, years ago Greek Yogurt became popular in supermarkets in the U.S. If you look at the nutrition label of a yogurt like Chobani, it contains roughly 4 teaspoons of sugar in one small container. And yet yogurt is advertised as a healthy food.
If you "quit sugar" in the U.S., you'll quickly realize just how many items at supermarkets have added sugar. I'm more concerned about "sneaky calories" then straight-up junk food.