When I was little, us kids were warned about the "Ding-Bat" that had a large ball of bone on the end of its tail, and sat on limbs of big trees, above game trails. It would swing its tail and knock out anything walking under it, then swoop down and drink its blood.
Whenever we played in the woods, we were always wanting to see a Ding-Bat. So we would look up before we walked under a big tree. While looking for them, we would often spot a Widow-Maker, which is a dead limb, that could fall at anytime.
This was our parent's way of making sure that we would look up often enough, and avoid walking under Widow-Makers.
The tale of Santa serves the purpose of teaching us that there is someone, and also many others, who know how to give, without expecting anything back. We eventually outgrow the story, but never the lesson.
Santa isn't on par with the Christian belief in Jesus, but both teachings render valuable services to our children. And the one doesn't appear to detract from the other.