This is an example of your nearly getting something right. There is a real need to be able to hire security or not, as individuals circumstances vary. That doesn't mean there is a real need for Police to be the security though, since police from the onset derive their money from threats of force rather than consensual contracts.
The problem with the police scenario, is they exist, (allegedly) to protect people, yet it is impossible for anybody to really protect people when those same protected people are forced to pay the alleged protector (even if they would prefer a different option) or suffer consequences. You should start your examination of the police at the beginning, lest you deceive yourself and become a hypocrite.