WAITER ASKS FOR PLATE WHILE EATING

I went in with my two children for a nice relaxing lunch. Two of our meals were served and the third meal came 20 minutes later as we were nearly at the end of our meals. Whilst i was eating, a waiter that was not even serving my table asks me if he could have the board that my meal was on and he will replace it with a plate. I losty appetite and sent what was left of my meal back. Few minutes later my sons meal arrives. I complained to the manager and she did not do anyting about it. She infact asked if i had ordered the third meal later on and not on my initial order (which i had not), seemed like passing the buck instead of being apologetic and solving the problem. Whilst my son was eating, there was a waitress and i was waiting for him, i saw a waitress digging her nose. What a terrible overall experience. I will never go back!