Do you tell a fellow diner if they have food on their face?

You’ve got a little something….No, not there. It’s just to the right (pointing next to the corner of your lip)…no, the other side…

The act of telling someone they’ve got cheese on their chin can be an awkward moment. You can wipe your kid’s cheek with a wet paper towel, but your boss will require a slightly more delicate touch. But where does your obligation end when it comes to telling somebody that have food on their face?