What Happened to Manners?

While hubby and I were out eating today, there was a young kid who was constantly whistling at a table near ours.  His grandparents didn't seem to mind, but it became really annoying very quickly.  

This made me wonder what happened to the manners that we were taught growing up?  Looking around, not only was this kid whistling, but one guy has his hat still on, and at other tables the kids were up and running around the restaurant playing.

Growing up, we sat politely at the table with feet on the floor, our hats were removed the minute we walked into a building, and whistling inside was not allowed.

I know things have changed, but it would be nice to see some manners return to our younger generations.