The Democrats and Republicans both serve the rich, and use the government to help them take advantage of We the People.
The Libertarians/Tea Party think that's inefficient.
If they get government out of the way, the rich can take advantage of the People directly - and save a lot of unnecessary paperwork in the bargain.
Libertarians want smaller government for the same reasons that crooks want fewer cops.
Libertarianism is the wolf of corporate fascism in the sheep's clothing of liberty.