Why do parents let their children run wild nowadays??

we live in an aprtment building and my husband is constantly having to go outside and tell kids to be quiet if they're going to play in front of people's homes (one kid even muttered profanity at my husband as he was walking away)....i love kids and understand that playing is important, but these kids scream at the top of their lungs...once my husband even caught some small children banging on our a/c unit with rocks......why don't parents watch their children?? do they not care about them, i mean these unsupervised children could meet any number of unsavory fates..?? do these people have absolutely no respect for others? what's the deal??