The thing about profit is that (for what I think are very good reasons) I consider profit to be one of the best/most important possible things that humans can produce.
In a completely free market, the more profit you create the more 'good' you are doing in a very real/tangible way. So thats why I have no issue with for-profit police services.
But again, there are a lot of underlying concepts/ideas that justify that line of thinking to me - and in their absence what I'm saying wont make sense.