I understand your confusion, but recall that in Protestant churches it is also common to refer to the religious leader as “pastor.” Pastor is the Latin for shepherd. Both in the Old Testament and in the New, there are references to shepherds caring for believers as for a flock. Men are directed by the Lord to shepherd their people. So there is no impropriety here, no usurpation of a title reserved to the Lord Jesus.
The last Lutheran Pastor I spoke w/, I called him a Shepard. He corrected me and said No, the Lord is our Shepard.
That’s when I said, okay, you’re an assistant Shepard and we laughed.