Let's see... There are the two American secular holidays (Fourth of July and Thanksgiving), April Fool's Day, Darwin's Birthday, Talk Like a Pirate Day and Pi Day. I work on Easter and Christmas, they are not my holidays by my traditional Jewish roots nor my atheism. I no longer celebrate the Jewish High Holy Days. Passover or Channukah.

When in Rome.
"EITHER ALL DAYS ARE HOLY OR NONE ARE, I HAVE NOT YET DECIDED."
Dorfl, Feet of Clay, Corgi 1997, p404, Pratchett, T.

I don't celebrate any holidays on my own. I didn't once my son was old enough to ask if he wanted to celebrate. I've always felt that if I took care of my son's emotional and physical needs/wants every day, there's no reason to celebrate a holiday. I had to celebrate with my niece once she moved in with me because her needs had been so neglected until that point.

it's called labour day , family day , boxing day , victoria day and thanks giving [ which is the celebration of the harvest to us in canada ] don't you have memorial day ?

Good grief-there are enough holidays already. I dislike celebrating the religious US holidays we already have, and mostly I dislike that US holidays involve eating huge quantities of food. Why? I hate fixing food I never eat, for people, waiting on them, cleaning up after them, entertaining them. In Thailand, I can attend constant festivals and just buy what I want from street vendors, without having to entertain anyone.