It's actually a very complex system, house and land ownership.
Say you buy a house appraised for 230,000 dollars. You add a few niceties, and get it pumped up to 300,000 dollars. You still have 230,000 dollars to pay off of your house but you now have 70,000 dollars you can pull out ANYTIME you want for anything you need, called equity. Owning a house is like having a security deposit on your life, basically, and can keep you afloat through tough times. You can also easily get a loan redone so you get that 1000 dollar a month 30 year payment reduced to a 1500 dollar 15 year payment if you get in at the right time, saving you assloads of money. You have to make sure you have a good loan officer or they won't know when to lock your rate though, meaning you can easily get your loan redone for more than what you wanted.
It's really complex.
A car is really just to say "hey look I got rimz ***** lolol". Getting a decent vehicle in cash seems much more sensible, but we're america: Land of the indebted, home of the politically correct white christian society. Most people don't give a damn about sensibility and live at least part of their life like they like.
Also, credit is very nice regardless. For instance: my uncle has a good 500 grand plus in the bank. He could pay his house, cars, and all debt off in cash. Instead he lets it float around. It keeps his credit up mostly and gives him a lot of extra spending cash each month.