My grad student friends generally don't work exceptionally long hours and their lifestyle isn't particularly affected by their lower pay, they just aren't able to save as much money.
I'm not really sure what your point is about IP, if you work for almost any company, any IP you create while working for them belongs to your employer. Pick a better university if yours doesn't give grad students any rights, here's an excerpt from the grad student IP policy at the local university (where a bunch of my friends are):
"As a graduate student, you own or co-own the intellectual property you create as part of your work for academic credit or a degree. You are entitled to publish the work, patent or copyright the work in your own name, as you or your co-creators see fit. The University has no rights of ownership and cannot use your work except for the purposes of academic review and evaluation."