As is traditional, I only come up with good comebacks after I am no longer able to use them.  So I am planning ahead.

I have decided on my standard responses when I am faced with a stranger who wants to tell me about my parenting decisions.  I shall now say a variation of:

Well, I wasn’t spanked and I think I turned out better than average.

Well, in MY day, we were taught not to be judgmental about other people’s parenting decisions in public.

And as a encore, my response to “well, you look like you have your hands full” is “full hands are much better than empty ones.”