SJSU was interesting in that for most residential students, if you didn't eat at the Dining Commons, you could take your ID / meal card to the Student Union or the Pub and get cash credit towards whatever you wanted to eat there. So, worst case, you could always get a couple slices of pizza or a two-piece fried-chicken meal for the same swipe of the meal card that admitted you to the DC.
I happen to know that's the case at Northwestern now, and they've always seemed a bit behind the curve on such things, so I assume it's the case at pretty much every university in These Modern Times.
That's also how it was when I was in school a decade ago. I can't remember if it happened every single time, but the school occasionally loaded everyone's student ID with $50 at the start of the semester. Otherwise, you'd add your own money whenever you wanted, and could use it at the student center, or at the library.
The college where I work offers the same option to students, and apparently faculty/staff as well (I keep forgetting to look into that). I believe your card may also be used at a few off-campus restaurants and businesses. When I was in school, there were rumors that my alma mater would do the same thing, but that never came to fruition. I'm thinking it's changed since I graduated.