Some people make noise when they eat with their mouth open. It's not scandalous, it's just ignorant and gross. It's always an utter clod that is so unaware of themselves just smucking and squelching away on their open mouth full of gloopy donut muck.

It's not a virtue to be so unselfcounscious. It's not about being ashamed or inhibited or in pathological denial of biological realities. It's about being fucking minimally considerate and just the tiniest bit self-aware.

Tell that to my asshole. I’ve tried training it to be silent on the shitter for near 40 years but it fails more often than not.

I had a friend growing up who ate with his mouth open. I fucking hated it. But he had problems breathing through his nose due to something with his soft tissue in his throat. So, you learn to ignore it.

It would be virtuous to not judge others based on some small thing they do that annoys you, just as you do things that annoy others.

I agree but only because that's the standard for our culture so somebody not doing it is probably being disrespectful which means it becomes offensive to others because it normally only comes from people with some sort of negative feeling or inconsiderateness for those around them. In some cultures, noisy eating is the proper way and shows you're enjoying the food. Same goes for clothes, toilet sounds, etc. It's a lot more repulsive seeing a human poo on the street than a dog even though it's not fundamentally very different.