Things that need to be said instead.
One of the problems with Paul's candidacy (and one of the advantages, when he does it right), is that it attracts a lot of oddball questions. The reason this is a difficulty isn't that these questions are terribly difficult to answer. It's that the actual solutions aren't the most obvious to the audience, or to the average "libertarian". Paul's effective mission is to popularize elements of a* libertarian philosophy, to essentially teach and maybe popularize. While some dramatic examples and thought experiments go along away (I thought the legalised heroin question from a debate some months ago was quite good), starting off with the idea that people who cannot afford, and thus do not purchase, medical insurance should be left to charity (or worse, left to rot) doesn't really have the impact of reaching and molding new minds unattached to the movement. It's an Overton window approach that won't have the effect of reaching and convincing people who disagree with stronger market based forms of health care delivery and insurance. And since there isn't really a median GOP type who actually supports more market based health care delivery and insurance, it is useless to try to stretch the gap out. The closest we tend to get in the US was a bill sponsored by a Democrat (Ron Wyden).
Paul's good about examining questions of "how" when it comes to foreign policy, particularly compared to his stage-mates in the GOP debate field. And he can be pretty good at attempting to explain "how" when media sorts start talking about the need to "protect" us against big corporations; essentially that part of the reason there are some of these big corporations is because they're allied with government already (crony capitalism). So starting off with the familiar "let them die!" trope (while not what Paul actually says is what the audience hears, either because it wants to say it itself or expects it in fear of us wacky folk) is a lot different than having a ready made "how" story to tell. Health care has massive distortions in price, and even availability because of large public sector spending. Which already accounts for roughly half of all medical spending. This is a feature that other Republicans tend to elide and ignore (see: keep your govn'mt hands off my Medicare). It's not surprising that the associated insurance would be already expensive for this reason. And it is made further pricey still because of large public sector meddling in so far as the types available, mandates inserted into them, etc. There's a great deal of standardizing or basic regulating that the government could do to help here perhaps (transparency, streamlining medical codes, etc), but the idea that the appropriate response to a government caused market failure is more government is kind of the most obvious philosophical retort for a libertarian to make to a question like that. It's not as complex a story as it could be, and maybe an example or two would help (for instance, NY state has banned HSAs, and it is thus one of the highest medical insurance cost states).
But it's better than giving the F-U mode response.
*- I would emphasize at this point that Paul's record and philosophy seems a lot more like "Constitutional conservatism" or paleo conservativism and he seems a lot more ethically motivated by things like objectivism (ie, the cult of Rand) rather than something akin to "classical liberalism". Nevertheless these things are, relative to the American political spectrum, very much closer to libertarianism than to modern conservatism or liberalism. Paul tends to annoy me with the Austrian economics tree and associated goldbug rants, and thus he does tend to say some silly things about half the time. But the other half he's at least saying interesting things. I just wish he would say them with a little more concern that most of his audience is always hostile and doesn't actually need to hear the most extreme reactions of even a quasi-libertarian mindset. The perfect cannot be the enemy of the good here. At some point we're going to need some pragmatic efforts to bring about at least some of these ideas into practice.