I just don't get it

I have never understood the way people swarm to the grocery store at the slightest mention of snow in the forecast.  We've been having big storms with frighteningly regularity, and as yet I have not felt the need to go grocery shopping because of the weather.  
I'm pretty sure Cliff and I could make it for a month without going shopping if we had to.  I can make bread and biscuits if we're out of bread.  I have a freezer full of good things to eat. I'm not milking my cow this winter, but I always have condensed milk and powdered milk on hand, just in case of an emergency; because when you're ten miles from the nearest grocery store, you can't stop in the middle of meal preparation and go buy something.  There are canned goods galore on the shelves, including several cans of tuna.  There's always plenty of spaghetti, noodles, and macaroni in the cabinets, and any variety of dry beans you can think of.   
This coming storm could be a doozy, but at worst, will anyone be snowed in for more than four days?  The road crews should have things nicely cleared off in that length of time.  
  
So, could someone please explain this run-to-the-store-oh-my-goodness-it's-going-to-snow phenomenon?  Did you not do your regular shopping this weekend?