No, situations like these do not require much thinking, either in advance or after the fact, to know how to address them. Simple good manners will suffice.
No, I would not have addressed these kids, because (a) I don't engage in political conversations with strangers in fast-food waiting lines and (b) I don't see them as doing anything other than minding their own business.
Or do you suppose you would be cowering in the back of the line afraid that you might get "a mouth full of broken teeth."
No, why would I be?
See, we've became a nation of wussies, afraid to speak up for what we believe in, and that is why this nation has become so p/c.
You seem to be projecting something here. Being polite and civil are not the same thing as being, as you so adroitly put it, a 'wussy'.
And p/c will be the death of this great nation, mark my words.
Either that or mouth-breathing neanderthals confronting otherwise peaceful citizens in restaurants.