Thanksgiving Day is that one day we set aside each year to express our gratitude. While I think this is a good idea, it's mostly a symbolic gesture because we really express our gratitude by our actions throughout the year. I think a more accurate term for it is "Thanksgiving Rewards Day," because we really celebrate the fruits of our thanksgiving by stuffing ourselves with turkey and watching football. Again, I think this tradition is fine, as long as we regularly express our thanks through our words and deeds. While I think JFK's legacy is hugely overblown, I think he got it right when he said "As we express our gratitude, we must never forget that the highest appreciation is not to utter words, but to live by them."
Yes, we need to live by our words, but uttering them can also be a great comfort to ourselves and others. The story of the thankful Samaritan has great meaning. As Jesus Christ went through Samaria and Galilee, “he entered into a certain village, [and] there met him ten men that were lepers” who “lifted up their voices, and said, Jesus, Master, have mercy on us.” Jesus told them to go show themselves unto the priest. “And it came to pass, that, as they went, they were cleansed. “And one of them, when he saw that he was healed, turned back, and with a loud voice glorified God. “And fell down … at his feet, giving him thanks: and he was a Samaritan. “And Jesus answering said, Were there not ten cleansed? but where are the nine? “There are not found that returned to give glory to God, save this stranger. “And he said unto him, Arise, go thy way: thy faith hath made thee whole” (Luke 17:12–19).