You "HURF DURF FREEEEEDOM!" types are so cute when you get agitated :-)
A fully free market cannot work unless people act rationally. As long as people do not act rationally 100% of the time, there will be a need for rules and regulations, otherwise it turns into "dog eat dog" very quickly.
The very core principle of libertarianism is "every man for himself", which quickly becomes "fuck you, got mine". So yes, it is perfectly in line with the libertarian mindset to sell blatantly overpriced goods by false advertising, to naive people who don't know any better.
The most insane idea (which is held by Ron Paul, among others), is that we should abolish all regulations on pollution and environmental controls. If people downstream get sick, they can just sue, right? Because no environmental effect was ever subtle and long-term, right? Increased cancer risk for generations would never happen, right?
Once you enter the real world where you can't just do what you want nilly-willy without caring about consequences, we can have an enlightened and fruitful discussion. Until then, feel free to wallow in your fantasy of a world where grown-ups can't tell you what to do, and you can eat ice cream for breakfast, lunch and dinner every day.