Meanest Mom Ever or, Mom of the Year?

A Mom is being praised and vilified on the internet because of what she did to teach her young 'uns a lesson.

Jaime Primak Sullivan bought her kids some ice cream at a Dairy Queen and then tossed it because they didn't say thank you to the clerk. She explained herself on facebook:

"So ... I am the meanest mom ever ... Like ... Ever." "Took the kids to Dairy Queen after dinner. They ordered their dessert choices and we waited about five minutes for them to call out our number. The young lady (maybe 17) handed each child their ice cream. Not one looked her in the eye. Not one said thank you. Not to her, not to me ...

So I waited. I counted to 10 in my head as they dug into their ice cream and the young lady just looked at me (probably because she thought I was hearing voices) and I watched as my children strolled out the door. I followed them outside where I calmly collected their ice creams and my kids watched in horror as I deposited them into the nearby garbage can. All three launched into mass hysteria. I waited. Quiet. Calm. When they realized I had something to say, they quieted down.
I explained that one day, if they were lucky, they would work a job like that young lady. And I would hope that people would see them. Really see them. Look them in the eye and say thank you. We are too old at 8/7/5 to move through our days without exercising manners and honestly basic human decency.
So today, I am the meanest mom in the world."

What do you think? I've known some abuelitas that could throw a mean chancla and plenty of short - fused moms but, does this punishment fit the crime?