While they were designed for combat, they are effectively the same thing that Brinks uses to transport money. They are meant to stop bad things from killing the people inside. They have 0 offensive weapons.
They are entirely defensive vehicles that have been used to rescue downed officers, civilians in harms way (gunfire), and multiple times in natural disasters where other vehicles would have gotten stuck.
While I get that they "look scary" to some people, they do have utility and come very cheap from the federal government that is trying to get them off their books. Local police pick them up because when there is a gunfight/hostage situation/disaster it's better to have one 5 mins away than an hour away.
I honestly don't get the outrage about them.