Sure, you are what you eat but more than that, to others, you are how you eat. It is completely alright to chow down your food however you want to at home or with close friends and family. But if you are traveling or settling down abroad, and sharing a table or any other dining space with others, things have the potential of getting a little more complicated. You might remind a Japanese friend of his or her grandmother's funeral if you rest the chopsticks the 'wrong' way, and you might just upset the chef if you ask for extra salt in Portugal.
While some are taboos, others have a reasonable explanation behind a particular table manner. Anyway, as a statement of your openness towards other cultures and awareness of the habits of people you are with, it is always nice to learn some of their etiquettes. With some effort, not only will you end up not offending anyone, you will also end up making friends quicker than you think.
Surprising, yes, but that's how they roll.
Design credits: Lakshya Vij