Parents! Would you keep a child in a booster seat if...?

They were right at the recommended height, but 16 years old? I'm just asking because my mon makes me sit in one and I'm 16. I feel ridiculous. I technically by law don't even have to wear a seatbelt in the backseat and here I am in a booster seat. I'm 4'9", which is supposed to be the magic number, but she claims I have to be over that height. So would you keep your kids in a booster sear in that situation?