Why is AT&T Locker being discontinued?

I love(d) AT&T Locker. I just recently renewed my service with AT&T without doing any shopping around largely because of access to AT&T Locker, one of the services I have come to depend on, which I just discovered was being discontinued. Naturally the guy at the AT&T store didn't mention a thing regarding this (im sure he had some idea of this given how much knowledge of the phones and network he did have). I want to know the reason for this, does it save AT&T a few pennies here and there or am I the only one out there that uses this?