OTOH, that sounds like a pretty darn good "intangible" to me and would certainly warrant further consideration in my book.
(a) If you are underprivileged, you might have time to volunteer somewhere, but typically supporting your family doesn't count as helping the underprivileged. Changing grandma's bedpans isn't volunteer work, and it's kind of exploitative to make that a major portion of your college application.
No, nobody at my school was doing this[1]. Top-tier schools leverage their massive endowments to provide substantial need-based financial aid. Basically their mission is to ensure, if you get in, that there is absolutely no financial friction to attend. In one high-profile instance Princeton University provided a full scholarship entirely from its own endowment to a formerly homeless undocumented immigrant who went on to become his class's salutatorian[2].
[1] except the cockroaches but that applied to everyone as many of the dorms were quite old.
While they worried about buying food and paying the rent, you "worked your ass off" doing homework in total safety and comfort.
But I was wrong. Poor kids who get into MIT ("Recipients of a Federal Pell Grant") only graduate at a rate of 87%. It's just the wealthy students with such incredibly high graduation rates.
http://web.mit.edu/ir/pop/students/graduation_rates.html