Parents: Please do your jobs

Just got back from a week long vacation to DC and the amount of badly behaved kids was appalling and all had parents with them. I'm not talking 0-6 yr olds either. I expect little kids to be badly behaved, but 8, 10, 14 yr olds etc should know how to act in public.

One example: getting onto a fairly full Metro train. There is an open seat, but a girl of about 14 has her feet up on the empty seat (she's sitting in a row that faces forward and the empty seat right in front of her faces the side). I motion my wife to the seat thinking the kid will put her feet down when she sees someone needs the seat. Nope. Kid was obviously upper middle class and her parents were sitting right next to her. Kid looked up at my wife and just left her feet there. I ask the kid to move her damn feet as the train is full. Her parents heard, still say nothing. I was about to push her feet off the seat when she finally moved them while acting all put out and sighing heavy. I let my wife sit down and mean mug the shitty parents. They did look a little embarrassed. My father would have told me to put my feet down as soon as the train began to fill up. He certainly wouldn't have allowed me to keep them up while people were standing.

2nd example: in American History museum in the Presidential history hall. We're walking through looking at displays and reading. It's pretty quiet as there is a docent led tour going on too. Well here comes these 2 kids shrieking and playing with the stroller. An 8-10 yr old is sitting in the umbrella stroller, while the 4-5 yr old is barely pushing him around. They ran into an older couple, a few walls, all while making loud shrieking noises. We're looking around and there are no obvious parents in sight. We move to the next room and the kids' mother is there and tells them to shush. Kids ignore her and run off into the next room. She doesn't go after them. Again, a very well dressed, attractive woman. I'm about ready to go yank the older kid out of the stroller when dad comes from a room up ahead and tells them to be quiet and tries to get the older boy (Hunter is apparently his name) out of the stroller. Kid tells dad no loudly and then both kids just laugh. Dad says fine and tells them to go with him back to the room Mom is in. I mean WTF?

These aren't the only examples, just the most glaring. Parents please discipline your bylittle monsters. No one thinks they're cute. I just think they're little assholes.
What shocked me is the amount of other adults who were clearly just as irritated as we were, but just ignored it.