I was wondering the same thing, so I spoke to samsung about it. They said it's because the 7 inch runs different firmware (4.1.2). They said it may be included in the next update. Lets hope.
I went to a Sprint store last night and got it. Actually, they didn't have any in store so they ordered it, I'll probably have it by the weekend! :thumbup:
I believe it just do not work I have a Galaxy S3 firmware 4.1.2 home and back keys light...on the Galaxy S4 back and home keys light up so why a newer product don't have it??