I thoroughly agree with you and consider this a safety issue. When you have a 160 pound back stopped by a 260 pound lineman, it can be very dangerous for a 270 pound offensive tackle, or another 160 pound back with a running start to use the runner as a battering ram to bash past the defense.
I'll admit to using the alternative approach, of considering progress stopped at the point the battering begins, which hopefully negates the purpose of the battering, for instances that are not as obvious or flagrant.