I have four kids. We were always too embarrassed to stay in the public place when our kids acted up. I never understood why other parents stayed..
I was 1 of 4 and now have 5 of my own. We never hesitated to remove one of ours from public when their behavior required it. We worked hard to establish good behavior and predictable consequences early on and like many have said, now rarely have to deal with it now.
What I like to do now, when watching some parent trying to appease thieir little terrorist, is point it out to my kids. Great training for THEM to be good parents to MY eventual grandkids.....