The people at that store would have had to have been pulling this off for several years. Most fast food establishments have been online for 5 years or more -- this means they're connected to McDonald's servers 24/7, so head office and/or the Franchisee would notice what's going on with the slightest of strange activity.
Even small towns have round-the-clock camera feeds.
After all that; they'd have to fudge the inventory for all these "mega-stacks" they be making
Where's Neckbeard at? I'm sure he can weigh in on this fishy-smelling story.