I couldn't have said it better myself K.
This is a major pet peeve of mine. I have 3 kids 13, 11 and 4 and they do not act like that while out or otherwise. My sister is known for this, she lets her kids do whatever they want and it drives me batty.. its freaking rude.
I have this look that I just shoot my kids if necessary as reminder and it stops them in their tracks. It wasn't easy getting them like this, as said above it takes training. Thats the problem, too many parents just don't want to be bothered.
Case in point:
I was at my cousins house and another cousin was there with her kids. The one kid was climbing on the kitchen counter and my Aunt told him to get down. His Mom just sat on her @ss. When we left my kids were in shock and couldn't believe they were even climbing on the counter... pretty bad when other kids are even :o
Now I won't lie, my 13 year old can be a smart @44 pain in the butt but he won't do it when we are out. I am always complimented on well behaved and helpful they are.