To me, it's about respecting others as parents. It's not about 'lying to your kid', it's about realizing that treating other parents to a random meltdown after school because Susie said Santa isn't real isn't ideal.
You can tell your kids the truth, just also teach them to mind their own business, essentially.
The ideal thing to do would probably be to tell the teacher/school admin at the beginning of the year that the child knows Santa isn't real and have the teacher pull them aside before the class Xmas party and reaffirm that your kid is so super mature for knowing the truth but since the other kids aren't as grown up as they are, they've gotta keep the secret.
You can definitely not do Santa but also find out ways not to make parenting your kid's friends and classmates difficult (because if you do, other parents will avoid you and you hurt your kid socially!)
What truth do they have to handle if you don't start with a lie?
We give gifts to each other on other holidays, birthdays, and even for no reason at all. Isn't that a better thing to teach a child to comprehend than a made up sky person who sneaks in your house after dark and who is constantly watching what you do, even while you're asleep?
