Chewing with your mouth closed???

Chomp chomp chomp. Chewing. It is a natural thing which we do everyday and being in a Western country, they do it with their mouths CLOSED. I had thought this seemingly Victorian age practice had gone the way of the dodo but a quick search on google shows me how wrong I am. Tons and tons of links about "How do I get my son/daughter to chew with their mouths closed?" or "How to master eating with your mouth closed?" And the weird thing is that people seem to be offended or disgusted by the SOUND of it which really boggles my mind. I mean, I could understand if I were slobbering drool all over the table but hey, food doesn't leave my mouth. It stays inside till it is swallowed. This phenomenon whereby Western people impose a mouth closed chewing policy really confounds and scares me because it shows the effect of a widely experienced cultural brainwashing. Well, obviously it doesn't only work one way. We Asians have lots of criticism about "decadent Western culture". So what do we do? When in Rome, do as the Romans do seems to be wise advice to follow. What does this tell me? Something I have always known; perhaps we are born free. And yet, society imposes and enslaves us. It is the only way to keep the majority of people from rioting. Not rioting is far from being happy, or even content. It seems humanity is so hopeless now that governments are simply trying (and some times failing) to keep the unhappiness level at "unhappy but sucking it up".