I am no fan of libertarians, but this is unfair. Cato, for instance, spends a fair amount of time and even a bit of political capital fighting against police militarization, civil forfeiture, and police misconduct. They also dislike qualified immunity, mandatory drug sentencing laws, the War on Drugs generally, and so on.
The problem is that you don't have to be a libertarian to fight those battles, and the vast majority of people who are fighting them aren't libertarians. Meanwhile, you do have to be a libertarian to carry water for the rich, especially on issues that even the country club Pubs wouldn't want to touch. So when people see libertarians, that's often the context. And over the past 20-30 years especially, libertarians have found it hard to find $$ support. The people who back them expect a certain degree of service on issues important to them. And thus do libertarians spend most of their time on the economic shit.
Libertarians aren't bad people. Mostly, they are just assholes, which isn't necessarily the same. Almost without fail (in my significant experience, at least), the loudest and most obnoxious members of any law school class are 1) a libertarian know-it-all who thinks Ayn Rand and Econ 101 teach all there is to know; and 2) a "progressive" poseur who wants to fight with everyone. But I've never known a libertarian who is attracted to "the cruelty is the point" politics of the GOP.