[Nothatspecial]

My family and I were eating lunch in the food court at THE MALL in Korat. Suddenly, without saying a word she gets up and leaves with the younger daughter.
Older daughter and I stay and finish lunch.
We're done and leaving the food court when we meet up with wife and daughter. They had been gone for awhile and I honestly thought she was done eating and went shopping.
My wife starts crying and wouldn't tell me what was wrong.
Later, when we were going out to the car my older daughter told me my wife was angry because she didn't get to finish her lunch.

To me this didn't seem like a big problem. If she would have told me what was wrong, I could have bought her a new lunch and waited for her to eat.
What should I have done ? Any way I could have made amends ? I guess you should know my wife is Thai. Did I breachsome kind of social custom here ?