Lesson in Verbal Etiquette

Let me tell you how a typical attempt to have a deep conversation about proper behavior and etiquette goes with an almost-four year old...

True story.

Setting: At the checkout line in the grocery store.

Ethan walks up to me and loudly asks why the teenage/college age (they all look way too young to me) boy who has just appeared to bag my bagged groceries has spots on his face.  Yes, that would be acne.  All I can think to say at the moment is: "Ethan, stop.  Shhh...." (while inadvertently glancing up at the boy in question to see what the heck he means...and making eye contact which means...he heard.) So on the way out to the car, we have this conversation:

Me: Ethan, if you see something different about someone, it's not nice to talk about it. 
Ethan: Why?
Me:  Well, it might make them feel bad. 
Ethan: How can we do that?
Me: Um...well...when you talk about spots on someone's face, it might hurt their feelings.  We need to think about others and only use kind words about someone.  If you notice something about someone's face that you want to talk about, you talk quietly to Mommy about it or don't say anything at all.
Ethan: Mom, can you back into the garage?

Well, I think the message got through, don't you?