Political compasses are a terribly misleading way of understanding political opinions IMHO, I wouldn't read too much into this.

Libertarians tend to be against state authority and all-in with private authority. They are market absolutists and see the expression of influence or power through market dynamics as not just OK but desired, since they consider markets to be meritocratic.

I would say you can be anti-authoritarian and pro-democracy (i.e. power is still exerted through a state authority, but the state is more evenly represented by the people)

The issue with libertarianism is that it only sees the abuse of power being that which is exercised through the state, but I think most people recognize that to be an incomplete picture.