I have issues with face paint but not with how it looks -- it often looks great and professional -- but take a ton of photos and you'll be less upset that it smears five minutes later.
My issues are the fact that face painters use the same paints and brushes on kid after kid at some big event. Hello, germs and viruses trapped in greasy paint that holds them right by my kid's nose and eyes!
For that reason my daughter always got something painted on her arm instead of her face. Most painters are fine with that and it's not really an unusual request. And best of all- the kid can SEE the artwork. Think about it -- with face paint the child cannot see how he or she looks!
My kid is 11 now and not interested in face paint except if it's part of a costume for Halloween, and then she knows we'll be doing it at home. She's old enough to think about the germ issues for herself and thinks it's gross now!