At HF or 6m, few hams use mobile antennas that are much longer than about 1/4 wavelength,
and you can match that with ...
But hams DO use half wave, or 2 x 5/8 wave antennas, or many other designs, on VHF/UHF,
and that is where the NMO makes these possible because it provides a ground connection
for the required matching networks.
OK, I've got your point; I've been misunderstanding what you were getting at. Sorry!
You're right, I've never bothered with anything other than a simple quarter-wave for VHF or UHF.