I am not sure how this works on CA, etc. My father came to the US on an H1-B in 1999. He was hired as a contractor by an agency that specialized in bringing H1-B software developers from the former USSR and India. He then had to go look for an actual job, since this company was simply a middle man.
After he found a job, he got his salary: about 1/3 of the reported number. The rest was cleaned up by the agency that brought him here. Eventually, he got his green card and left the agency, but what this implies to me is that an H1-B worker may not get that much of the salaries reported on this list. However, as I mentioned, I have no idea what percentage of H1-Bs are hired through thrid-party middle men.
That sounds like an all-round illegal scheme. First, in order to get a H-1B you need an actual job offer, and with the application the employer is certifying that they will pay that rate. There is no such thing as a "middle man", you can't simply apply for an H-1B for someone with the intent of them going looking for a job when they get here.
It's not quite as crude as you made it sound. The programmer works for company X, with a fixed hourly rate. He has the H1-B with that company, and they are the ones who are sponsoring him. Company X contracts out to Company Y who pays company X for the services provided by the developer on-site. Company Y pays Company X, and Company X in turn pays the developer. On paper this looks legitimate to me.
After he found a job, he got his salary: about 1/3 of the reported number. The rest was cleaned up by the agency that brought him here. Eventually, he got his green card and left the agency, but what this implies to me is that an H1-B worker may not get that much of the salaries reported on this list. However, as I mentioned, I have no idea what percentage of H1-Bs are hired through thrid-party middle men.