Exactly, I wouldn't consider a job posting that doesn't mention salary seriously either. It reeks too much of a job that wants to take advantage of you while paying peanuts.
Almost no job postings mention salary, and most jobs are filled. Certainly the hundreds of thousands of bigco job ads don't post salaries, and startups don't either. Government does.
you leave out a very important segment of the job market, which is recruiters - who know salary ranges (part of the information they receive) and can match them to salary expectations before proceeding.