[Americans celebrate Christmas.]
Some Americans celebrate Christmas. Others do not.
[I find Old Navy/Gap advertising offensive as they list every imposter holiday under the sun as being equivalent to Christmas.]
Since Christmas was basically stolen from the Pagans, you're right--there probably aren't any imposter holidays equivalent to Christmas.
[It's arrogant and insulting.]
Which is more arrogant and insulting?
1) Old Navy employees recognizing all holidays equally, regardless if they personally celebrate them or not.
--OR--
2) You claiming that your holiday is superior to all others, and bitching about it when others don't celebrate it with you?
[We won't give our business to this organization anymore!]
Fine, if that's your choice. You have the right to do so.
Similarly, it's our right to laugh at you.
Don't let the door hit you on the way out.