What is going on today?

A rarity occurred today the likes of which I have never seen. Some person was rude to the professor in two of my classes today. The first instance happened in my environmental science class. A woman's cell-phone rang so she ran out of class to take the call(kind of rude there, but thats not really the issue). When she comes back the professor asks to see her after class. Then all of a sudden this loudmouth woman sitting next to me yells out, "why doesn't she have to leave class? That other girl had to leave class when her cell phone rang. Thats discrimination". And at that point I just thought to myself, 'oh, here we go....' The professor calmly asks her to leave as she is being rude. The woman refuses and continues on, "I'm not leaving. You can call security and give me a zero, I know the drill. I'm not moving".
Why?? Why must people behave this way? In what manner does this concern her at all? If the girl who had to leave when her cellphone went off felt it was some sort of discrimination, she could talk to the professor privately after class and resolve the issue. Who does this woman think she is, some sort of hero or vigilante, who stands up for the little guy? No, this is a woman who didn't take her crazy pills before coming to class. Now, I am not some teacher's pet or anything, who always gets straight A's and defends the teacher no matter what. But the man never raises his voice. He is never rude to any student, and treats everyone with respect. So why disrespect him in such a manner and waste everyone else's class time? He had to leave for about ten minutes to go get the Dean or someone who later came into class and asked to speak to the woman in private.
This is not middle school or high school. That woman is about 40 years old. Her daughter goes to the same college. And yet she behaves in such an immature way. While talking to someone else she suggested "if that guy wants to read his newspaper, he should be allowed to read his newspaper". Yes, why don't we all just do our own thing while the professor draws doodles on the board. Ridiculous. So thats that story.
The other one isn't really important. The point is, if you have some sort of problem, don't make a spectacle of yourself arguing with the teacher in the middle of class. Or something like that.