Actually, all the R&D done by grad students is paid for by you. The vast majority of our funding comes from the US Gov (DARPA, NSF, NIH, etc), a bit from private sources (Gates Foundation, etc), and a tiny, tiny amount from internal funding. Funding grants pay our salaries, purchase equipment, pay for lab space, etc. Pretty much the only time a professor will get money directly from the school is when they're starting out, in which case they'll typically get 200k - 1 million to get a lab started. Undergrad tuition pretty much goes to pay for non-research profs, and administration.