When I put a job req in with HR for a new position we needed filled they butchered the requirements we wanted but they are the pros... So in my case we weren't look for a perfect fit for the description. I'd say that goes for a lot of listings out there where they don't expect to find an exact match but are looking for someone at least strong is some areas and can demonstrate the competency to catch up in areas where they may be lacking in experience.
It depends on the field but degrees can often be substituted for years of experience. In the tech world is a nice requirement to get H1B candidates though... Look at the graduates from top tier programs and US citizens are a minority. H1B aren't necessarily cheaper (often they aren't) but they are easier to retain because its harder for them to leave the company for the next best thing/quick salary raise because they are dependent on their sponsorship. Otherwise for newer grads its often easier to get significant pay increases by switching jobs every few years if you have what it takes.