There is a poster put out for LE officers saying to check their ammo. It shows a number of factory goofs, including upside down primers, crushed cases, and overseated bullets. Of course, checking ammo would not find other errors, like cases with no flash holes, no powder charge, etc. It is a good idea for anyone to check ammo that may be used for serious purposes.
BTW, that upside down primer, if loaded and fired, would not have caused any real problem, just some smoke on the breech face and maybe a bit of dirt in the firing pin hole. Of course, in a bad situation, it would not have done any good, either.
Jim