Almost all holidays are religiously based. Christmas, Easter etc. I celebrate those.
Also, Eastern religions tend to be deeper on a philosophical level than the monotheist religion. A festival about inner personal peace is more interesting than the celebration of someone's birth imo.
It's nothing to do with religion. I don't have to personally be paying tribute to the reasons behind the day in order to enjoy the company of my family and bask in our shared enjoyment. I'm an atheist, not a killjoy.