sometimes you dont have space for a keyboard on the desk , or you want to just move quickly along... most people who name stuff from hardware dont use crazy names, more like D1, D2, V1, V2 etc.. so it actually ends up being quicker than using a keyboard. i understand its not like this for everyone, but i have easy access to my mpc, my microkorg, sp404, turntable, and midi keyboard (i have a small desk) and have to use a battery powered wireless keyboard that i move around..when im making beats i HATE having to use it (same goes for the mouse.. but ive made a little space on my desk for that.. ill get a bigger desk eventually though, just wanted to point out an example of why naming/renaming could be beneficial from the hardware
same with the godddamn editzones "all, current, multiple" and the fact that you have to use a mouse

with all that said - i do like using the mouse for loading files, browsing breaks, loading vsts, etc.. but use the q links to tweak parameters most of the time