You can do pretty well with next to nothing. I spent three months hitchhiking and couchsurfing my way through the US and Canada, covering roughly 20,000 miles and staying with dozens of hosts. I started with $700 in my account, and still had a few hundred left by the end of the trip. Had I wanted to be more frugal, and not get 'local food' when someone suggested something especially good, I probably could have gotten by with less.

So it's true that you need something....but you can do it with little enough that $25 can be a significant part of your budget.