Actually, when a "Delay" is given in the system during the background check, the salesperson doing the check doesn't see why, under the system is just comes up "Delayed" and that is it. When this happens, the bureau in control of the background checks has 7 business days to declare a "Pass" or "Deny", and after this 7 day period in defaults to a "Pass". The associates at FF should be aware of this, as they have to legally sell you the gun after the grace period, however, it isn't ENTIRELY their fault, as they can't control what the background check kicks out, and you would most likely have received the same result at a different store.
I used to work at a Gander during college, and sometimes ex-military folks with a security clearance would trigger a "delay". Not a big deal, an inconvenience yes but it's not the store's fault.