In the days of my youth, in school, it was against the rules to eat in class, but during lunch any student can enter the classrooms and eat there in peace.
Well, that's why they invented a little thing called a lunch break.
It kind of bothers me when people are eating during lecture. A lot of people in my college love to eat their lunch during class time and use their lunch break to do something else. Why? Because screw logic. That's why.