May libertarians ARE anarchists. Anarcho-capitalists also call themselves libertarians and voluntarists. Free Talk Live, the most popular libertarian radio station has hosts that are nearly all AnCaps who care about the NAP more than outcomes, and so forth.
And in a libertarian Utopia, it is truly Caveat Emptor - let the buyer beware! Personal responsibility, no nanny governments!
Even in libertopia, there may be independent voluntary consumer protection organizations (not funded or enforced by the state) which sellers and buyers might associate with or otherwise utilize to ensure positive trades.
Anarcho-capitalists aren't anarchists. It is self contradictory to have a society that is controlled by capital owners (capitalism) and one that is controlled by no one (anarchism).
And in a libertarian Utopia, it is truly Caveat Emptor - let the buyer beware! Personal responsibility, no nanny governments!