What I DON’T understand is why people say “have a nice holiday” for THANKSGIVING, which is a secular holiday (albeit with religious overtones), which even us nonbelievers celebrate. I still say Happy Thanksgiving (and Merry Christmas to anyone I know or suspect of being Christian). I am also NOT offended when a Christian wishes me a Merry Christmas.
Me too, I still say Happy Thanksgiving in greetings as much as possible. You are right about this day being a secular holiday with faith overtones. Went to mass this morning for a special Thanksgiving Day gathering at my parish church. There was a good turnout with music included. Wish during the sign of peace the Happy Thanksgiving greeting. :)