To me, its an homage, to Leo, and the great men and women of the Fender Musical Instrument Company. Its a point of cosmetic completion. And its a traditional emblem, in the traditional place.
Under no circumstances would I try and pass the guitar off as "actually made by Fender", and neither would it pass any but the most casual inspections.
You can build up a Ford Tbucket
like this one, that has large FORD logos in various places, although there are probably zero Ford parts in it.
Or you can build up a Harley
like that one, that has a few Harley parts (I think the front rim is still original!), but the motor, transmission, etc... all made aftermarket for customization. It still says "Harley Davidson" on the logos.
Why do folks do that? Probably for the same reason I do... or at least thats my take.