But you don't believe that screws directly over and into the inseam will cause damage?
True enough. But once they are removed...esp. screws in the inseam...what do you think the impact on the inseam will be going forward. Do those holes or that damage strengthen the shoe? Do they make it easier for a repairman (or even the maker) to retain or recapture the original structural integrity of the shoe? What does it mean to the end user that his shoes may have damage that doesn't come from ordinary wear and tear?
I guess if we don't think about it too much or too deeply its doesn't make any difference at all.
Those are double (or triple?) sole shoes. Assuming standard 5mm outsole thickness, double sole is 10mm.
A 3.5mm nail is not going to penetrate 10mm thickness double sole, thus not going to touch the inseam.
EDIT: and of course, it can, if a 5" nail/screw is used. But everything can happen doesnt mean it will/should.