St Nicholas was a real man from Asia Minor, who having been brought up religiously, devoted his life and wealth to charitable giving. The use of St. Nick as the symbol of giving at Christmas is a good and fitting honor.
He gave in the way he was taught to by his beliefs, honoring God by helping those in need in the way God's gift of Jesus helped a world in need.
The modern image of Santa is off track but the basic lesson of giving and doing good is at least still there. and at least that opens the door for more to be learned.