Thais may feel that hugging and kissing may reveal too much of their emotional state, may in a sense risk a loss of face. Or as Nirish said in post 6, "...my family aren't at all tactile and my parents were fairly much of the Victorian mind set of it's crass to "show emotion" and always show a "stiff upper lip" etc..."
Thai student returns to family after several years abroad. Wai's of course, but aside from that just a gentle pat on the shoulder by mom or dad. No hugs or kisses.
And whatever happened to the romantic sniff-kiss? No lip kissing when I first came to Thailand many many years ago, though thankfully most of the Twilight boys are not hesitant about it now.
American friend with Cambodian bf reports that he experimented with some sniff kissing and his bf was immediately aroused.
All of this appears to be perfect material for someone's D Phil dissertation. Looking forward to that.
BTW, after reading Nirish's post above I had to double check to see who wrote it. No evidence of his usual stream of consciousness, to hell-with-grammatical-agreement-and-spelling writing. Completely intelligible. Maybe that's an example of his weekend posting?