If you get a pair of bespoke shoes, the fitter (in this case M Mandonini, who I presume is the guy in the apron) has no choice but to get down on his knees when drawing the customer's outline, taking his measurements and (if used) placing the foot onto an ink pad. Later during the trial and final fitting, he is again kneeling down to inspect all the details. There is virtually no way around the fitter kneeling: it's a question of practicality, not a sign of deference.
I remember, yonks ago, the old Maxwell shop in South Audley Street having a "throne" (raised by two steps) set-up for fittings. That might have enabled the fitter to work from a little stool, But as fitters work differently (some prefer the customer's weight 'off', others 'on'), for weight on he still would have needed to kneel down. No idea, if there are still firms who use a throne for fittings (and obviously only in their own premises; they are not likely to travel with a throne to their trunk shows in the States or Japan.
When I had my bespoke last made by an elderly man, for whom kneeling down was obviously difficult and painful, I felt rather guilty about putting the poor man through this procedure. But there was no way it could have been done without the fitter kneeling down,.
I remember a television chat show with that old raconteur the late Peter Ustinov, talking about receiving his knighthood. One of the Queen's officials enquired prior to the ceremony, whether Ustinov was able to kneel down. His reply (delivered barking and grumpily):
"Yes, I can kneel down...........but I can't get up again!"