It is so maddening I know. This may not be suitable for your hallway, but I've put carpet on the corners of my hallway as that's where they always scratch. They now use that, especially when I come they both run to a bit of it to scratch. It's a marking thing for them you see, she is just marking her territory and it becomes a habit after a while. My other furniture is also scratched, so I guess you can't only limit the damage.

Mary