I agree. No one forced that lady to take the Metro. If she doesn't like the "no eating," "no litering," "no cell phone" rules, then she should take a cab.
This is an honest question (not just to you, but to everyone, myself included). If you, personally (or anyone else reading) had approached the metro escalator with the last bite of a candybar in the wrapper and were told not to take it downstairs, would you have (a) shoved the last bit in your mouth and gone on downstairs or found a trash receptacle to put it in? Not a baiting question, anyone, just wondering what most folks here would do.