several months ago, my neighbour uncle scolded one of his children.
one of his children was influenced by other students and prayed and thanked god before having the family dinner.
my neighbour was pissed off and scolded his son and shouted: it is limpeh who work like dog that you have food on the table. not your God
I have seen a Christian couple (presumably on a date) hold each other's hand and bowed their heads before giving thanks for their food. Go figure.
It's one of those silly man-made rituals. Christians fear the social disapproval from other believers if they see them not say grace before a meal. You should have seen the deathstares of some of them if you dared to drink beer in front of them e.g. at a wedding dinner. Sit somewhere else if you feel uncomfortable or 'stumbled in your faith' you self-righteous pricks.
Personally, I am all for being thankful for food. The hawkers who toiled to prepare it, the waitresses who endured hardship to serve it to your table, the farmers and fishermen who braved the outdoor elements to do their job, and the animals who sacrificed their lives for your plate. A moment's pause to thank them all before eating.