I called and asked whether a 13 year old could get multiple cartilage piercings at once and the lady was very polite and said that she would not. Is this a store policy or just a personal preference?

Its a policy at almost all tattoo and piercing places due to reliability. They can get shut done by health and city people for breaking required rules. I was able to get piercings young due to a friend who worked at freakshow but that's it.

I'm sure it's a policy in general. When I was younger in a different state, you couldn't get a cartilage piercing unless you were 16 with a parent