Yes, because we still fly the -300 and -500. I hate it, but it's to keep them all similair for us idiot pilots who can't read old and new instruments without getting confused? When they park the last -300 & -500, hopefully they'll flip the switch and let us use modern glass displays.

I flew the 757-200 with steam airspeed and altitude gauges and the 767-400 with glass speed/altitude tapes in the same day. Why can't I do the same on the 737?