For me it's probably that as an Indian, I eat most food with my hands without utensils.
Most foreigners get freaked out that Icelanders eat rotten shark. (We eat it rotten, because it's very poisonous when it's fresh.)
Kissing among male and female :) example you are meet a friend(man) first thing you shake his hand and kiss him in cheek :) female do same thing.
Do you know pork blood pudding in Taiwan? I heard it was elected as the most 10 disgusting foods in the world. It is bound to horrify so many foreigners who want to taste Taiwanese food.
For Chinese, there are many. Eating stinky foods, obsession with traditions, and speaking Mandarin, an artificial language while despising our real native languages.
Very interesting so far. I have heard that many cultures do practice kissing of the opposite gender even when only friends.
