Ignorance is not bliss

I just went to Wawa before to pick up some milk. On the way out, there were 2 guys just standing around the door. As I walk towards my car, I hear one of them say, "Oh look, these people come to Wawa! Maybe it means something in their language." Then he proceeds to make weird sounds, my guess he was pretending to speak in another language. So I turn around, glare him down, and say, "Excuse me? I hope for your sake that you weren't speaking to me!" He looked stunned and his friend quickly muttered, "Oh, he didn't say anything!" as he pushes them both back inside. In all honesty, if he continued to say things, I wouldn't even know what to say back. If I were to curse and ridicule him, I wouldn't be any better than him. All I wanted was to get some milk in peace, is that so much to ask for?