You have all at some point read my rants about children running wild in the grocery store. It is not cute, nor is it darling when your badly behaved child is running around, bumping in to people, touching/dropping/breaking things they have no business touching or picking up in the first place. As I tell my own children, unless you have the money to pay for it, you have no business picking it up. This saves me from having to pay for something my children broke. This is called parenting. This is called teaching your children how to behave.
The same can be said for guests in your home. My children were raised to respect their elders, and to behave in public and in other people's homes. We have all had "those" children in our homes at some point. You know the ones. These are the children who throw balls in the house which almost always end up breaking something. These are the children who stand in the middle of a glass table (yes, this DID happen, and YES, I DID have a freaking heart attack) These are the children who write on your walls. And these are the children who break things, on purpose, just to get attention.
When you do not teach your children how to behave, or how to respect their elders and peers, you are not doing them any favors. You aren't. You are teaching them that they can do whatever they want to, with little or no consequence. this is not a good lesson for them to learn.
I have also noticed that these parents also fail to teach their children responsibility. Responsibility can cover a wide range of things, from how to be responsible for their own actions to being responsible for doing their own chores. You see having children do chores is something that teaches them not only that they need to help out in a household they live in, but how to take care of these things when they grow up and move out. Doing your 25 year old son's laundry, while he sits in the basement playing video games complaining that you did not buy him Twinkies is NOT teaching him responsibility. The reason your 25 year old son lives in your basement, unemployed, is because you failed somewhere at teaching him responsibility (this can be interchanged for a daughter, I am not being sexist, there are many irresponsible daughters too)
Teaching them how to behave takes time yes, it also takes patience. If you have neither time nor patience to teach your children how to behave, why did you have children in the first place? Put your drink down long enough to spend some time with your children. Teach them how to behave. Teach them how to be responsible. Children also learn through example. Are you setting a good example for your children? I'm guessing not if they behave badly and irresponsibly.