A reasonable thought, but sadly wrong. It is true that when the blade is flat the molecules will migrate to the edge and so the effect may seem to be that as all the edge is affected at the same time that the sharpness is not affected. But sadly this is not so as the micromolecules fall off the edge leading to a general dulling of the sharpness and a potential staining of the work bench top. They can also be attracted to any chisels within about 93mm of the plane blade where they congregate at the edge leading to general chisel dulling as well.
So lay your planes on their side and keep turning them on a regular basis and all will be well.
You have not been charged for this advice.
Cheers, Phil