it's more the practical concern of having to turn off some or all pedals in between songs in order to tune effectively.
The above is what make most sense as well other than wanting to measure the fundamental, to have the tuner all the way infront.
if just bedroom wanker, it prolly doesnt make much difference, but if need to play shows often and tuning inbetween songs, heh, no one prolly like to step dance frequently, just to tune.
Of course tuning still can be done, but then, just like picking my nose, why would i wanna put my arm round my head before my finger can penetrate my nose when i can just poke me finger straight into my nose.