Not everyone is as flexible or small enough to get down & get under, I'm afraid.
Jacking up may not be necessary, but it gives an opportunity to take the wheels off for the task.
Agree, I've got a full bumper with the low number plate so it's near impossible to do it on mine without jacking up. It just makes it so much easier
I also use it as an opportunity to turn the wheels and give the inside of the wire wheels a wipe and quick clean
