It wasn't a ban on it entirely. They wanted to limit the size in which you could buy it for personal immediate consumption. You would be able to buy a 2 liter bottle, but they wanted to ban 2 liter cups.
This is a misconception that has led to much confusion. A choke hold is banned, but it is not illegal. The officer only broke departmental rules, not the law. It was still unwarranted at the time the officer used it.