When I was in physics grad school, some 20 years ago, I was paid $11K/year. As a single male with no dependents, living in a room which cost $200/month, and walking distance from classes and work, it was quite doable. Others, married and/or with children, had it more complicated. Some students did get welfare. The plan was that after graduation we would have access to much better paying jobs. But some of my friends, PhD trained in chemistry or physics, still found it difficult to find a job in their chosen profession. Many ended up with postdoc positions, making more than the adjunct professors mentioned here, but still with little money and little job security.
One may say they have "zero pity for highly educated people who do not understand the basics of supply and demand in their chosen job market" - and bear in mind that I'm talking here about people trained in the sciences, and not humanities which is oft smirked at for its dearth of job prospects. But the thing is, we as people get to decide what failure means. We don't need to let one bad choice prove ruinously disastrous.
As jseliger's link points out, I, as a 21 year old who outside of a few summer jobs had never been outside of the academic environment, really did not understand the job market and options available to me, so made my decision on rather limited information. I hadn't even realized, for example, that graduate schools paid TA salaries. I thought I would have to apply for scholarships like I did for my undergraduate education.
It worked out well for me, but it also felt like a lot of chance was involved. Lady Luck could easily given a worse roll. I do not see my success as purely my own achievement. I do not want my failures to be my own cross to bear, and nor would I wish that on others.
Yes, I believe in funding a strong social safety net.