Libertarian views are far less extreme in many ways than modern Republican views, and often align rather closely with progressive/democrat views. In fact, the libertarian ethos evolved from classic liberalism, including support of LGBT issues, racial and gender equality, and a largely non-interventionist global view.
Republican-voting libertarians are in some ways worse than normal Republicans. Unlike normal Republicans who simply don't believe that their policies are violating people's rights, Republican-voting libertarians freely admit that the policies they are supporting (their stated position is against the policies, but they still support them with their votes) violate people's right, but they go along with them so that they can get a tax break.
