That's not always true. My mom wanted me to get a BMW 328i convertible but I wanted a Mercedes CLK 350 convertible. So I threw a tantrum and I got the car I wanted. So minors do have a say sometimes!!
Only because your mother DECIDED, out of the kindness of her heart, to let your voice matter.
But your mother was the one who had to make the decision and the purchase.
Also, if you think this is the kind of community that cares one way or the other about what kind of car you pretend your mommy bought you, you're seriously confused. You should find a different website to post on. One that's more pretentious and will actually argue with you about your faux-internet life.