thats a poor comparison for the education, the average american isnt doing the same kind of work but the comparison for pay is based on the sectors of employment so they are well compensated. And many h1-bs attend undergrad in their home countries and grad school in the US to make them more appealing to US companies, so they are "more educated" because they have the masters but a masters is only 1-2 more years of school depending on the program so it isnt really a big gap.