Tape-in and Tape-out ports

Why do so many preamp manufacturers still provide Tape-in and Tape-out ports? I doubt if they expect folks use them for hooking up a tape player. Some even still have a tape monitor switch on the front panel. How do you guys use these ports and has anyone noticed a difference in sound quality if the tape-in port is used for something else like a CD player, etc.? If the tape-out port is just like another output, e.g., drive a separate amp or a powered subwoofer, etc., why not just call it Output?
Been meaning to ask this question, albeit it might sound rudimentary.