While my heart goes out to people like this woman, life experience has taught me that sometimes the person has the money, but is too cheap to spend it.
Aren't we talking about a train here that you have to purchase a ticket to get on in the first place? This isn't a homeless bag lady. And she had the money to buy a ticket. They should kick her off the train for doing that stuff.
Having the money for a ticket doesn't always mean having money for food. I rode in Coach with a couple who'd spent their last bit of cash, except for maybe $10, because they were moving from IL to AZ to live with her mother. They'd lost their jobs and home and had nowhere to go. Coach on Amtrak was the cheapest option (they didn't have a car). The lady was pregnant, and they were wearing holey sweats. They had one backpack with one change of clothes and their toothbrushes. We spent a lot of time in the SSL together; they were very nice.
If I hadn't just spent all but $30 on a train ticket myself, I would have given them some money for food. I felt really bad that I couldn't, but that was literally my last $30 for the next two weeks. They had some snacks and such with them, but no actual food.
It's not good to assume. I know it's easy to get jaded, and there are people who fleece the system, but I'd hate to deny someone food just because I think they're cheap. It's not right for one bad apple to spoil it for other needy people.