I also HATE the uncontrolled screaming children thing too. Now I have a child, mind you, so I'm not speaking out of place. But I would NEVER allow my child to run around, getting into things, screaming, throwing fits, or anything of the kind. I work in a doctor's office, and it always amazes me how some parents just let their kids run around in the exam room, opening up drawers, climbing onto things, whining LOUDLY that they want a sucker, opening the door of the exam room to look into the hallway, all while the doctor is trying to talk. And yet the mom just sits there carrying on a conversation like nothing's happening. Ugh!
I used to hate this with a passion, then I had a kid, an autistic kid, let me tell you first hand there is no controlling them when they decide to act up. Most parents arent really ignoring the kids, they are just tired, embarrased and mortified. You can't yell at them for everything, sometimes you have to pick your battles. For me my sons autism makes it hard to do anything a normal person takes for granted, even something as mundane as going to the grocery store can be a daunting task. My husband and I no longer go out to dinner with our son because we feel bad for the other diners, now he does not act up all the time but he can be annoying to others. I no longer look down upon parents with unruly kids, I empathize with them. I do however think that parents should apologize to others if it's obvious to them that the kids are annoying or upsetting others, better yet they should have the kids do it.