Technical Inner fender well?

Does anyone know what the reason for the lip on an inner fender well is? Is it just a matter of manufacturing ease? In the upper Midwest many cars have severe rust in this area. Can the lip be eliminated as in AA-B?See drawing
Thank you
Dan

 

The rolled or shaped edge does two things. It gives a finished appearance, and adds strength to the fender stamping. No reason the drawing on the right wouldn't work, and help eliminate a place for moisture to sit.

 

It also supplies an edge that can be spot-welded without requiring finish bodywork for paint.

 

Thanks guys
Dan