Why do the stately homes of England have names?

Answer 1

English manor houses were sometimes named for geographical features. Sometimes they were named after particular farm fields or road crossings, fords or bridges. Sometimes the owner of a manor house gave it a name he simply liked. Though it is not medieval, Jane Austen's book, Pride and Prejudice provides a few names that illustrate this. Hunsford is clearly named for a Ford crossing a stream or river. Longbourne takes its name from a stream or brook, which is what bourne means. Netherfield is a low field. And Lucas Lodge was given its name by Sir William Lucas, who had just purchased it.

Answer 2

The names identify them. Given their size and locations, one would hardly expect a street name and house number ...