EDIT: I see the idiocy to which this reply was aimed as been removed.

Mmmm, yum. Delicious back-alley "underground" yoghurt. "Please, don't mind the urine smell on the way to the counter and no, of course we don't have any Botulism today."

And this right here is where the anarcho-libertarian "logic" breaks down. In reality there is no "just go underground" where "just" means "do something with trivial or non-existant transaction costs." In reality, there are a whole host of problems that come with running a food service business that's outside the purview of the health authorities. First and foremost, you're also going to be outside the purview of a lot of potential customers. And the few who can see you well enough to find you are also going to see a whole host of warning signs before they reach the point of sale. Unless you're selling something so addictive that people will risk their lives for a fix, good luck running a viable business on the few who are foolish enough to hand over their cash.

Remember, the point of regulations is not to eluiminate dangerous, fraudulemt, or otherwise undesireable conduct entierly. It's to drive up the cost to the point where the number of people doing whatever they're doing is low enough for the hazard the represent to fall below some commonly agreed-upon threshold.

Obviously, the toxic idiots who find themselves getting marginalized by effective government regulations would love to get back into the mainstream. These are not people governed by any internal moral compass. They're fundamentally sociopathic, and they'll push back in whatever way they can. One of their favorite tactics is a form of psychological warfare where they try to convince people that efforts to police them are a waste of resources since they'll never be 100% successful, so honestly, why bother at all? Gun nuts use a variation on this tactic wherein they point out that some aspect of the mass shooting du jour means that some generally sensible legislation wouldn't have stopped that particular killing. And therefore, they conclude, all legislation is pointless and doomed to failure, so again, why bother?

Rejecting the obviously absurd assertion that anything not 100% effective is 100% ineffective, it's clear that efforts to limit abusively self-serving conduct can make themselves worth the expense, even with a success rate that's well below perfect. It's not about each an every incident, after all. It's about creating conditions in which mayhem and death are statistically far less likely. Statistics 101.

So yes, there will still be problems in even the best regulated environment. But they will be fewer and further between than they would be in some lawless free-for-all that only the staunchest libertarians would see as paradise.