This thread reminds me of an incident that happened many years ago when I was a kid of 11 years. My best friend Phil...who was 13...and I went to the Saturday matinee's nearly every week. I looked older than Phil. The admission price was 35 cents, and 25 cents for kids 12 and under. I always paid 25 cents without incident, until one day the cashier asked me my age. I told her that I was only 11 but she wouldn't believe me. She said that if I wanted to get in for 25 cents next week, I would have to bring my birth certificate.
So I did. Next week I presented her with my birth certificate. Her response?? "How do I know this is you???"
Sometimes people just believe what they want to believe.