Do any anarcho-capitalists object in principle to the rule of petty tyrants in HOAs, for example, even though HOAs are de-facto governments? Is such authority okay simply because it is "private"?
On the other hand, can a good case be made that such non-governmental entities are subversive in the sense that they provide alternatives to government institutions?
I find myself in the middle on many such questions, but still believe the primary goal is abolition of the state. Many tiny private governments and city-states would amount to an extreme decentralization of power, which is why a break-up of the United States through secession, though not eliminating the state itself, would be a good first step on the journey to ultimate liberty.
Anarcho-capitalists will normally, and quite correctly, object to the "love it or leave it" argument for the state. But their grounds for objecting to "love it or leave it" is only based on the idea that it isn't the state's just property (and the implication of this is that it if *were* the state's just property, then the "love it or leave it" argument would suddenly be valid). What's more, they tend to neglect the failure of "love it or leave it" in any other context (such as that of an individual proprietor). From my perspective, the problem with "love it or leave it" does not merely reduce to the state not having a rightful claim to ownership, but it is problematic for the even more fundamental reason that arbitrary claims of absolute authority over others derived from territory are not justified in general. The problem with authority cannot simply be reduced to a question of who owns what.
In relativizing and subordinating liberty to property, hardline anarcho-capitalism ends up looking like a rather hollow creed in the sense that it does not fundamentally object to authoritarianism. Rather, by implication of its own norms, whether intended or not, it ends up justifying authoritarianism on the grounds that it occurs on so-and-so's property and that it's the proprietor's "ultimate decision-making power". This blurs the line between liberty and authority by making it dependant on ownership - if you don't have ownership, you more or less are stuck submitting to the authority of those with ownership, and if you do have ownership, everyone else's liberty ends where your property lines begin.
If this is what the heart of the social anarchist critique of anarcho-capitalism is, then I must confess: I agree with the social anarchists on this general point (although when things get more specific, some notable disagreements emerge). Granted, some anarcho-capitalists tweak their theories to avoid such an authoritarian implication (and I would therefore want to avoid strawmanning at least to that extent), but this should be the logical implication of absolutist propertarianism and an indication of what happens when one fetishizes property and contracts to the point of absurdity and self-contradiction. And in the context of such an implication, combining absolutist propertarianism with anarchism is indeed a gross contradiction in terms and anarcho-capitalism deserves the derision that it normally gets from traditional anarchists.