That's basically asking "why don't they just throw away all their social connections and uproot their lives more than they already are"? Where you live isn't just the building you inhabit.
How willingly would you be to pick up and move in this situation?
Maybe I am misunderstanding something but is seems foolish to me to sit in a single location and complain that the right economic conditions for my success are not at my current location and refuse to move (especially ironic since we live in a capitalistic market economy, jobs are constantly changing and resources moving around).
This is a large-scale socio-economic uprooting. Many of them lack marketable job skills and the necessary finances to allow location portability.
We're experiencing a very large shift in financial wealth where the level of poverty in the country is increasing at rates not seen since The New Deal and that's the entire point: the Bay Area is an extreme example of this where economic disparity is so extreme. Add to that the socially minded nature of California and you have those people who "complain" of the lack of a social safety net at the Federal level or even a lack of a fair balance of distributing economic wealth fairly.
edit:
And our "capitalistic market economy" is anything but capitalistic, in fact it is predatory upon the poor and economically disadvantaged. [1],[2],[3],[4]
[1] http://reason.com/archives/2015/04/26/american-capitalism-vs...
[2] http://www.bbc.com/news/blogs-echochambers-27074746
[3] http://opinionator.blogs.nytimes.com/2013/09/17/making-money...
[4] http://www.huffingtonpost.com/2010/03/17/social-immobility-c...
https://en.wikipedia.org/wiki/Poverty_in_the_United_States#/...
It did, this has improved, however it's structurally temporary. The effects of it are that it's also continually displacing larger numbers of the middle-class as our trade policies are moving what remains of our higher paying manufacturing base, what used to make up that lower to middle part of the middle-class blue collar workers, to lower paying countries.
So, if you think, with your single graph that poverty isn't increasing you're not looking at what's really happening structurally in the US economy and with all of the relevant data around you.[2]
We have College tuition that is unaffordable and an aging, out of work, unemployed, or underemployed workforce, with skills that have not kept up with the rapid change in the shift of American jobs and poverty truly is on the rise.
[1] https://www.statista.com/statistics/200463/us-poverty-rate-s...
[2] https://www.wsws.org/en/articles/2016/09/03/jobs-s03.html (Uncertain how credible this site is)
2) You bring up a lot of other issues that are certainly real problems but they are mostly claims about what might happen in the future. That makes them speculation not fact. And sure, your speculation might end up being true and some of those speculations could lead to an increase in the poverty rate[A]. But you should be careful to frame what you are saying as a prediction about the future not a statement about something that has already happened in the past.
A. Personally I think you're wrong. But that's speculation too!
What evidence do you have that these people are too foolish to understand our economy? Or too stubborn to do what is needed in order to succeed?
"Several homeless families whose children attend local schools told the Guardian that they had considered moving to cheaper real estate markets, such as the agricultural Central Valley, but there were no jobs there."
Buy why not look evan farther? The US is much larger than California. There are places which much cheaper costs of living in the midwest and the south. Seems stubborn that you must stay in California.
But if they were guaranteed a life in Illinois or North Carolina, maybe they would move? You and I don't know, but there is no reason to suspect they are simply being stubborn or foolish. It's entirely natural and rational to want to live, with your kids, in roughly the same region continuously.