We can. We also have 2hr standby, more 2hr standbys than QRS.
Perhaps flight ops plan better?
Perhaps flight crew are better motivated?
Who knows, and what new arguments/discussions will prevail.
What I do know is of the occassions I've been called from QRS and the occassions that other crew have been called form QRS which has prevented disruption. I also know of an occassion when 4 crew failed to make a HKG report because of an accident on the roads, there was no QRS available and the flight crew came close to running out of hours. We were fortunate that the 4 crew, because of the delay, made the flight. However for a while it didn't look good.