The problem wasn't that they were joining with several others to thank God for a meal. They were crafting long, drawn out prayers that were meant to make themselves look pious and holier than thou.

Would you be willing to apply your argument to prayer in corporate worship? I think there would be a stronger temptation toward Phariseeism in a prayer meeting than over a plate of food.

True godliness is a sincere feeling which loves God as Father as much as it fears and reverences Him as Lord, embraces His righteousness, and dreads offending Him worse than death~ Calvin