Here's a cool article from StudentSoul to follow-up tonight's (WWD)^2
And here are some reasons I've noticed for praying before eating (there are more, for sure, but here're a few):
Thanksgiving --- God, you provide for us - salvation, love, community - even food!
Worship --- Let our eating be considered worship of you, Jesus, not anyone else!
Protection --- God, sovereign over the universe, protect us from our food!
Health --- God, work a miracle and make this Pop Tart healthy!
Tradition/Solidarity --- Father, we join with our global, historical family in Christ and pray before eating.