My sister told me when I was young that Santa didn't exist. But I had already figured out that the gifts from "santa" had my mom's handwriting on it so.... I found out naturally
But it wasn't a huge disappointment.
I like the fact that you're saying that Santa REPRESENTS the spirit of giving and receiving. He can act as a reminder for that and when people see him everywhere, he reminds people of family and getting together and sharing. THAT can cover religion, personal belief and everything else I think