When I think about how underpaid production crews are, I think about how people like Ryan Seacrest are overpaid.
Wouldn't it be awesome if an actor sets aside a portion of his/her million dollar salary to be paid to crew members? Or you know, a raise would do.
I think therein lies the problem of exploitation of labor. The people on top keep the money to themselves -- drive sports cars, hire drivers, live in mansions -- while the crew works their asses off for dirt and don't even get paid on time (in some cases).