Few piano players need all 88 keys. The lowest notes can be muddy and overpowering, and the highest can be too bright to be pleasant.
Especially when playing in a band, there are frequencies occupied by other instruments, so a good pianist can fill the gap in frequencies. For example, there is often little need to play down low when a bass guitar is already filling that frequency.
Just because all 88 keys are available, it takes great skill and experience to know the right frequency range to play in. I think it’s the same the role we play in trams. Just because we can operate at a certain frequency it doesn’t mean we have to.