Most large retail outlets will probably opt out of this initiative. A big part of their revenue model hinges on the "impulse buying" which occurs as you wander throughout the store looking for your items. There is a reason why no major department or grocery chain (that I am aware of) has a store directory at the front like most malls do.
However, if crowdsourcing is allowed this could become major. I and 20 other people could all map out the Walmart (for example), upload the data, and then whatever matches in 80% of the submissions would become part of the "map".
If enough people did that it would almost force the major chains to participate, if for no other reason than to maintain control of their maps.