You'd have to ask each one of them individually. But it's unlikely they burdened themselfes with that firepower after going to the expense and trouble it took to acquire and the right to carry it, for no reason at all. So you tell us what agenda you imagine they have.
What you imagine 'knowing how to use it' includes is for you to say. But until that knowledge includes how to reliably distinguish a mass-shooter from a citizen firing in defence, proven target accuracy of a high degree while moving under stress, and ability to rapidly assess danger to bystanders beyond their target, I'd say they don't 'know how to use it' in the sort of situations we're discussing.