No he wouldn't have to be an idiot, the law is clear. If the person has reapplied and has the receipt for his application, the license he holds is still valid. What part of that do you not understand?
If nobody is going to accept the law as its written, then all the effort and bullshit that GOAL and others put into getting it passed was all for nothing and it might just as well be repealed for the useless waist of taxpayer money that it is.
If a sale is made with the proper paperwork shown, an expired license within the grace period and a receipt of reapplication or a copy of the reapplication then there is notheing wrong and no FFL is going to be under any burden. Jesus Christ....some people are their own worst enemies when it comes to making things difficult.
Are you next going to say that if you are caught carrying your gun on an expired license (with a receipt of reapplication) within the grace period that you are carrying illegally? Get a grip....thats what the grace period was enacted for.
Think about what state this is, and think about how gun owners and gun dealers are demonized and then think about how wise it would be.
The grace period, as I understand it, was so that you could still possess your guns with an "expired" license, rather than having to give them up to a friend or whoever until your new permit arrived. Yes, you can make the case that you are still "legal" for those 90 days, and by extension of logic should be able to buy guns and ammo under those conditions, but think about the FFL. If he loses his FFL or any local or state licenses, he is out of business with zero income. This is like a liquor store accepting something other than standard ID for proof of age. Is there a statute-defined official receipt that shows someone applied? How is the FFL to know if what they are being shown is real or not? Why should the FFL risk his entire business over one sale?