Brainpolice:
I disagree with your take on what others mean by thick libertarianism, though you may have an understanding of it that differs from theirs.
Charles Johnson’s 2008 essay: “Libertarianism through Thick and Thin” begins with these words:
“To what extent should libertarians concern themselves with social commitments, practices, projects or movements that seek social outcomes beyond, or other than, the standard libertarian commitment to expanding the scope of freedom from government coercion?” (my underline)
Here is how Johnson describes the essence of the issue:
“…the question of general principle has to do with whether libertarianism should be seen as a thin commitment, which can be happily joined to absolutely any non-coercive set of values and projects, or whether it should instead be seen as one strand among others in a thick bundle of intertwined social commitments.” (my underline)
So Johnson is clearly talking about what position libertarians, as libertarians, should adopt with respect to additional social concerns or projects being part of libertarianism besides voluntary consent, or the non-aggression principle, or the private property principle (i.e., whatever is considered by the individual to be the primary principle of libertarianism)
The fact that people already do add other concerns to their libertarianism, as part of their libertarianism, is separate from the question of whether we want the explicit goal of libertarianism to include such additional values, or whether we want the explicit goal of libertarianism to be “shedding” such values towards an ideal of libertarianism which over time (as these additional values are uncovered in discussion and analysis) approaches an ideal of political liberty.
Perhaps the ideal of political liberty cannot be precisely defined so that it means exactly the same thing to all libertarians. In fact, it seems that this is the case. But Johnson is clearly defining the issue as whether we want the concept of libertarianism itself to hold a number of empty parentheses “(…)” into which, as part of libertarianism, we will insert other cultural values besides political liberty.