Old people and their houses

I don't understand why old people who can no longer live in their houses should be allowed to keep them and borrow money from the government instead of selling them and paying for their care with the proceeds.  Well, I do understand, it is because it is thought that that is what they want, and old people tend to vote more readily than young ones do.  But, really, if the relatives want to hang onto the house to inherit, then they should look after its owner.  Keeping houses empty for years is anti-social when there is such a housing shortage.