When I was a kid my grandparents owned a local resturant in town called "The Burger Shoppe"... sadly it closed a couple years after they passed away. However, I remember going with them here all the time before the shop opened each morning and since the actual restaurant (which use to be in front of Big R) was torn down, this place is really all I have that reminds me of that time.
The cache itself should be easy enough to find. Its off a backroad and the store closes fairly early, muggles should be to the minimum once its closed.
Have fun! Shibby!