Not everything is yet cheap enough to run on 10-50k of savings. Take semiconductors for example.
Some software technologies are also quite expensive to develop, not everybody is doing web apps, thanks God :-)
I'm 39, married, have a 7yo daughter, but luckily no mortgage. But I have $425 on a savings account to balance off having no mortgage :-)
And I'm throat deep in a startup for 2 years already, it's just a beginning.