I am a little judgemental of it as my family are suckers for it. It can be easy to fall into the habit of quick and easy food and you can pass it onto your children. It upsets me when I see very large people eating in a fast food place with very large children. It upsets me when kids ask for food and the parents say 'just microwave a pizza' etc.
However, I am aware that in my mind I am being a hypocrite as if someone is aware of what they are putting into their body and they exercise and stay slim but still enjoy a lot of junk food then I'm fine with that. So it's not the food itself, it's when you let the food become so important to you that you choose it over your health. I.e there's a family of 10st people and a family of 30st people in KFC. Which one are most people likely to judge a bit without knowing anything else about them other than the fact they both happen to be in KFC right now.