For that matter, why aren't all the "teens" pronounced like ten-one, ten-two, ten-three,...?
In French, the number 99 is spoken as "quatre-vingt-dix-neuf" which literally means "4, 20, 10, 9" with the understood meaning of "4 times 20, plus 10, plus 9."
Back on topic: I think roller disco is making a comeback and usually is peaceful.