I don't want to wade too deeply into this firestorm, I just want to correct you on a couple things.
This isn't unlike grad students who work in research labs or for professors doing research for papers. In the case of the former, the lab gets multi-billion dollar grants from the government. In the latter case, the professors are paid six figure salaries. In both cases, the students get a "free" education and little else.
Per the NIH (National Institutes of Health), which is the largest source of government money pouring into high level biomedical labs, OSU has brought in $67,957,973 in grant money for 2014 thus far, and brought in $131,126,886 during 2013. OSU brought in $48,862,000 during 2013 from the NSF (National Science Foundation), which is the other large funding source (DARPA and others can and do award research grants, but on a national scale they distribute much less to universities than the NIH or NSF). So in total, from the two primary funding agencies OSU brought in a under $200 million during 2013, as a point of reference.
The point of that data is that no individual lab will ever receive anything remotely close to multi-billion dollars worth of funding. The very best labs in the nation can, and do, pull in multi-million dollars worth of grant funding (though they are an increasingly rare beast these days).
This may seem like a minor point, but if you're going to have an argument, one might as well utilize the available data (all of those figures can be found through the respective NIH and NSF reporter sites).
Also, at least within the biomedical sciences, graduate students also receive a stipend on top of free tuition. For example if you are accepted into OSU's Biochemistry PhD program, in addition to garnering a free education you will also be paid a yearly stipend of $26,502 (which you can find on their website's FAQs).
I doubt any of this information changes the thesis of your argument, but coming from this arm of academia I just want to make sure that when people toss these examples out that they're tossing out accurate information. So, grad students who work in biomedical labs are going to school for free and being paid a modest stipend for their efforts.