Not sure how someone gets burned by not seeing the salary range. That would come up in the first five minutes of talks with the potential employer.
HN does not enforce NYC laws. Nor does it enforce Colorado laws, or any laws regarding jobs including salary ranges. Whether YC/HN have an ethical responsibility or not comes down to one's ethical position. Laws do not necessarily equal ethics.
Personally I would ignore job postings that leave out crucial information, including salary ranges. If we all did that (i.e. behaved according to our professed ethics) companies would post salary ranges just to get applicants. Compelling companies to post salary ranges by law may have some underlying logic I agree with, I don't know for sure. Compelling HN or any other public forum to enforce those laws (which vary and change by jurisdiction, with numerous exceptions) seems a stretch to me -- I would rather see the job posts and decide which to ignore and which to respond to rather than have HN try to enforce the patchwork of local laws by hiding postings. Once you get into the moderation business you have to invest a lot of effort in that and still you will piss off a lot of people.
Okay? But this law exists in other places too.
>Why not contact the company and politely ask for the salary range?
Because its not their responsibility to make sure some random corp is following the law? They're just getting burned by the effect.