Then why do you think the founders wrote the Constitution and Bill of Rights then? Probably because they saw how rights can be stripped, not just by a government entity, but anyone in a postion of control or force, because they have a desire to do so... Eliminating government is not gonig to stop those who seek control and force and have the means from doing so.
If you have a constitutional government, then there is nothing at all contradictory about an entity guaranteeing to you that no one will infringe on your god-given rights to life, liberty and protection of your property. How is it "in it's nature a violation of them" if you have an accountable government that doesn't abuse it's power (being accountable). If the police protect my property from intruders and don't infringe on my liberties or property, how can't the two be mutually exclusive? They can if they're as local as possible and accountable, but private industry cannot guarantee the same accountability when they have massive conflicts of interest not to.
Not to mention, as I already have plenty in other threads, that handing over security and trials (that are supposed to be by your peers, not hired jurors that may have a conflict of interest or be corrupted) to private industry is an absolutely terrifying concept.
The writers of the consitution gave very limited powers to the government, and that is because they saw how terrifying it was when the government did not guarantee those basic human rights, and let any powerful entity exploit them just the same as they do with excessive "safeguards".