Front axle sleeve length vs bearing to bearing flange distance ????'s

[TwoManyXS1Bs]

... the worst case tolerance stackup of NEW wheels...

I've seen provisions like that in mass-production factory settings.
Sometimes cheaper to have the assemblers do an added step (the *tweak* or *fudge* factor), than to implement tighter tolerances on all the individual parts.

..Best bet when using a spacer... is having the correct spacing...

Absolute ditto.

Fine tuning factory fitments also works well in gunsmithing...