@JPB,
Oh my! The very NOTION of acting out in a restaurant would never have occurred to my sister and me! I think, had we considered it, we would have thought the earth would open and swallow us!
There were no fast food places and our first restaurant was a HUGE deal...I think I was maybe five or six.
Up straight we sat, the table was innocent of elbowage re us.....
I ordered chicken in a basket, and was traumatised beyond belief when HALF A CHICKEN appeared, with accompanying vegetables AND A BREAD ROLL!
Used to extraordinarily coercive techniques and frosty atmosphere at home if the plate was not cleared (my sister and I had hotly debated and different techniques aimed at minimizing the perceived size of food we could not fit in) the sight of a meal I knew I would not be able to come anywhere NEAR eating was a horror!
My mother noticed and said it was ok if I couldn't fit it in. My similarly horror struck sister also relaxed.
Such pleases and thank yous to the waitress! Such praise of the largely untouched food! Such elbows to our sideness! Such lack of a crumb spilt! Such correct placement of the cutlery in the hands, in the not finished position, and finally in the finished thank you, position.
Such closed mouth chewing, such polite talk, such "please pass the ......s" and "may I pass you the .......s"