When libertarians talk to non-libertarians, many times it turns out that we actually have most of the same values, but radically different IFF criteria. Unlike the liberal-conservative spectrum, this is a spectrum of who you consider to be the greatest enemy of freedom: privileged citizens, or government. I fall way the hell down in the government-as-enemy range, but far enough from the end to think we need a small government to enforce laws against theft, assault, and breach of contract. Other people identifying as libertarians can be further from the end, or full-on anarcho-capitalists.
I'd like to set aside discussion of specific policies and the imperfect mechanisms of individual protection that exist in regulationist and libertarian-capitalist systems for a moment, and just explain to non-libertarians why we at the gummint-hating fringe think you're all insane:
When you talk about Gilded-Age robber barons oppressing the influenceless poor immigrant workers and invoke long hours, low pay, unsafe conditions, deaths from lack of medical care, and mind-boggling gaps between rich and poor, understand that very many libertarians agree with you. There are some who think that the market will perpetually fix these problems, but most of us (myself included) do understand that these abuses happen and are terrible.
But you're proposing to fight the worst-case scenarios that enemy threatens to bring by empowering governments, whose track record for the last century alone includes worst-case scenarios (often perpetrated by governments that the people thought they controlled right up to the last moment) of death camps, gulags, Great Leaps Forward, Rapes of Nanking, world-shattering turf wars that slaughtered people by the tens of millions, campaigns of genocide that killed far more, suppression of free speech and association, widespread civilian disarmament, enforced discrimination against racial and sexual minorities, and perpetually increasing universal surveillance, to say nothing of the everyday regulation of shockingly minute aspects of our private and professional lives that occurs outside the worst-case scenarios. Selfish monocled capitalists can create a great deal of suffering and unfairness. Powerful first-world governments have, within living memory, created hell on earth again and again.
In short, it's utterly incomprehensible to most libertarians that you would have more fear of an enemy that often ends up putting economic pressure on you to accept deals that aren't in your best interest than of an enemy with a terrifyingly bloody rap sheet that will literally force its rules on your public and private life through threats of violence.
tl;dr - We share your concerns about the troll who raids the city and carries off some of our children. We just don't think it's wise to suggest we scare him off by giving a dragon the run of the city. Your belief that the new type of dragon-training harness (guaranteed to work this time!) will keep it under control does not give us much comfort.