When minimum labor costs get too high for valuable or popular work, we end up with a lot of "volunteers." This happens all the time in science and medicine. In general, minimum wage hasn't had an impact on this (yet). Young scientists understand that working on a high profile project or in a "real world" clinic is good for your career. There's already enough downward pressure on scientific wages to prevent even the most jaded PI from offering a minimum wage position to paid technical staff. That all said, the average (non-graduate, but paid) student lab worker at UCLA makes $14/hr, with a $9/hr minimum. $15/hr is above the minimum salary for graduate researchers on campus. (Not picking on UCLA, their salary info is public and easy to search.)
So, we're getting into territory where minimum wage laws are putting cost pressure on scientific work. Interesting and a bit sad.
Will this even apply to schools? The federal and state governments usually don't apply all labor laws to universities.
I suppose University of Washington has the same issues. It would be nice to think that some of the more bloated administrative budgets would take a haircut to pay the student workers a bit more. It would be very sad if it simply became normal for young scientists to "work" for free their first few years.