Obama might have been busting on the elite attitude of his fellow Senator or he might be demonstrating his own elitism. Who knows?
Obama recalled a conversation he had with another senator who was giving him grief about working for the meal ban. The other Senator questioned to Obama, “What do you expect me to just start eating at McDonalds all the time?”(via)
Obama recalled his response, “You get paid $160,000 a year, you can even afford Applebee's, you don’t even have to stoop so low as to eat at McDonalds.”
But he did it in front of many who probably make it a habit to stoop to eating at McDonald's.