That's a great response!
I wish I was like you and able to be witty like that.
One time when dh was wearing dd1 in her sling an older lady come up to him and started cooing over dd. Then she started to say something but she was speaking Russian so I had no idea what she was saying. Dh starts saying something to her (he speaks Russian) and she got all huffy and stormed off. He said that she was pretending to be nice but she was really saying nasty things about us having her in a sling. She said something like, "shame on your parents for putting you in that. You don't like that do you". I guess dh said "shame on you for being so rude" and that's when she stalked off.
I hope that taught her not to do that to someone else. You never know if someone can speak a second language. lol.