Why empty folders don't import to eclipse project ?

I invoked tortoise svn client to checkout 'c' language project from subversion repository. Checkout is successful. All folders/files and empty folders for storing derived
objects are in the checkedout folder.

I create eclipse workspace. Then, I create empty 'c project' in eclipse.

I import checkedout project to eclipse as follows:

From eclipse main menu, File - Import - General - File System. I browse to folder in windows explorer that contain the checkout project. I click...

Why empty folders don't import to eclipse project ?