I am an only child and I think my parents feel that I am going to automatically inherit because of that. However, from what I know of my extended family, I think it is very important that they have a will, because I KNOW that I'm going to have relatives coming out of the woodwork claiming that the house and land is THEIRS! My mom's younger brother has already said as much - said that he would inherit the house and land from my parents. I also have great aunts and uncles who claim that the land is theirs - and even that my parents took what was theirs away from them! It could get ugly...
Now granted, when (and if!) I do inherit my parents' house and land, I'm immediately putting it up for sale, and using the money to buy my own home. I do not want to live where my parents live. I grew up there and didn't like it then, and would really not like it now. I will keep some of their belongings for sentimental value, but I don't want the upkeep on a home and land that is in an area that I don't want to live.