Because it tastes gross, and 9 out of 10 people agree with me about that that. Majority rules. Is this a republic democracy or what!? Lots of things taste bad, though, so why broccoli? Broccoli also smells bad. And worst of all, if even a tiny bit of this bitter vegetable touches something else, it leaves a nasty broccoli flavor behind. It’s a food of mass destruction, and so it must be eliminated.
In order to ban a food, it is easier to get it done if you can conjure up a health danger that results in higher costs to society. Unlike soda, broccoli doesn’t contribute to obesity, but, surprise, there are medical reasons not to eat broccoli. Turns out broccoli is a goitrogenic food, which can disrupt normal thyroid function by inhibiting the body’s ability to use iodine and lead to hyperthyroidism. Supposedly if you cook the broccoli, even light steaming, its goitrogenic quality is inactivated, but, as we know, people cannot be trusted to cook it so we need to ban it altogether.