When I was a child, my parents warned me not to tell my non Jewish friends that there is no Santa Claus. I never did, but somehow, they eventually did find out. Some confided in me that although they were disappointed, what really hurt was that their parents had deceived them. I have always avoided Jewish parallels to the Santa Claus story. In many homes. parents tell their children to watch the Cup of Elijah during the Seder, as the Prophet Elijah will soon be coming to take a sip. In less traditional homes, children are sometimes given gifts for Passover, and told that they are from the "Passover Chicken". My guiding light in all of this is the Talmudic dictum "the seal of G-d is Truth".
As I wrote in my Passover series, the custom of not eating kitniyot (legumes, later extended to most seeds), was originally an aversion of twelfth century housewives to cooking lentils during Passover, for fear that the recently introduced system of crop rotation might result in wheat becoming mixed in with the legume. Opposition to this innovation was widespread in rabbinic circles. Rabbi Yechiel of Paris said "It must be stopped before it spreads". Rabbenu Yerucham (1290-1350) called it a "custom of stupidity". ROSH (1250-1327), perhaps the foremost of Ashkenazi codifiers of the medieval period, called it "an excessive stringency". Nevertheless, after a few generations, the origins of this custom became forgotten, and it was assumed to be a rabbinic enactment.
Today, with better information retrieval systems, we now know the real origins of this mistaken tradition. Many rabbis, especially in Israel, have come out in favor of the abandonment of this tradition. Most rabbis, however, urge the continuation of the kitniyot ban, because it is "tradition". Even more insidious, are the private statements of many rabbis that "OK, it really has no basis. But if we tell people that, they will come to disrespect rabbis, and jettison even real halachot."
I was very upset last week when I read some postings, even by members of this group, to the effect of "Oh, what's the big deal? Can't you go for one week a year without rice and beans?" That is not the point! The point is that we have Biblical laws, rabbinic laws, and legitimate customs (according to RAMBAM. customs are only legitimate and binding, if they were in force by the time of the demise of the last Sanhedrin, in the fourth century.) With kitniyot, we know where and when it came from. We know that it was opposed by the rabbis, and we know how it came to be extended way out of its original proportions.
Instead of fearing that people will come to disrespect the rabbis if they find out that this custom is without basis, perhaps their respect will grow when they see the rabbis' emphasis on truth? Is Judaism a religion of folkways, or the continuing reverberations of the voice of the Living G-d at Sinai? It is perhaps comforting to celebrate holidays the same way our parents and grandparents did. But can we call that Judaism? Does G-d dictate our observances, or do our ancestors? If the latter, then I would recommend that you look into Confucianism. If G-d's Torah is not at the center of our Faith, is it perhaps Santa Claus? Food for thought. (Pun intended).