Lost images and LRCAT file

[sullins]

I inadvertently had Carbon Copy Cloner overwrite my current hard drive and would have lost several hundred images from a trip if I hadn't had the import backed up. However the LRCAT file still had the empty folders showing in the library view. Why didn't the old LRCAT file overwrite the newer one and eliminate them too? The images seem to be truly gone because they are not in finder.
Thanks