For those of us that are not religious, the presumption that we are obliged to participate in what should be primarily a religious celebration is far too often dismissed. I can assure you that we understand the cultural relevance of a celebration that we have witnessed every year of our lives and I assure you that the positive, social aspects are not lost on us. You'll probably find that we do in fact enjoy and participate in the tradition to varying degrees in part due to that appreciation.
What some few non-atheists fail to appreciate is that repeated coercion is not only unfriendly, but is insulting and demeaning. They wouldn't be as vigorous in pursuit of my participation were I, for example, a Muslim and yet don't seem to understand how disrespectful this is. They correctly expect and enjoy the right not to be bullied on the basis of belief and still seem to think that the holidays are a free pass to do exactly that to others. Presumably they mistake my refrain from faith as a lack of belief; yet my convictions are strong and they still receive my forbearance.
I would ask them to show me the same consideration.