Child support

Im wondering for all of you that say child support should be used however the person receiving thinks is best. Why is it ok for child support to be used on bills such as rent water electricity when those are things you would have to pay for regardless of having a child or not? There are people who pay all that stuff on their own because they dont have a child and dont have child support coming in to help pay for that. I get a child needs a roof and food and clothes. But in all honesty isnt it the food and the clothes and child care or medical bills the cost of having a kid so shouldnt child support be used for the things that the child needs. Not bills that you would already have to pay even if you didnt have a kid.