Writing Assignment: What Would You Do?

If you have ever watched the show What Would You Do? then this should be a fun and easy exercise.

You are at a local dine-in restaurant, nothing fancy, maybe a Big Boy, Denny's, Friendly's, or just a simple Coney Island. The lunch crowd hasn't arrived yet so there are just a few people seated. A  lady is sitting a few booths away. She has a young child with her, probably around five or six. While the woman is chatting away on her cell phone, her kid is running up and down the aisle, almost knocking the waitress over several times. The mother never once looks up or comes to collect her child, who is singing in a loud voice now as he/she marches past the other diners. Do you take action, sit idly by and fume as the child's obnoxious behavior gets on your nerves, or slap some money down on the table and get up and walk out?

What would you do?