Well, they fill out papers and get teaching assitantships to start. They then fill out papers and get food stamps (true) and everthing else they can get. They learned how to fill out papers and how to find what was up for grabs. They were very good at it.
I don’t know how things are done in California, but around here (SC), yes, you can get a teaching assistantship to help you through grad. school and then work your tail off, teaching, grading... doing everything the professor in charge of the course is too sorry to do himself/herself. The pay barely allows you to survive, and I don’t know anybody who applied for (or got) food stamps.
An assistantship is a job. So they are trading work for the school in return for reduced tuition. I never heard of a free graduate school education anywhere. You should get your facts straight.