Why is libertarianism so infallible?

Libertarianism is the inclusion of every sapient being into the decision making process and all that logically follows from that. Utilitarianism is the objective of ensuring the most happiness for all sapient beings and all that logically follows from that. Sometimes they compliment each other, other times they contradict.

Discuss.

Libertarian parties are full of anarchists, crackpots, and demagogues. Most sane people think the idea of voting for libertarians is laughable.

Many people have fear of bad people who will anal their mothers and steal their video games. Thus they will vote for Statist "Law and Order" political parties.