This is the very reason I am far from thrilled when the local WalMart remodeled and took out the fabric/craft department.
I may not be biggest fan of their fabric (no offense to anyone), but it was the other stuff like buttons/zippers/etc. that was important to me. Plus they are open when my schedule gets absolutely crazy.
I now have to think and plan very carefully because it is basically 1 hour 1 way to any store that carries that type of stuff. There are times (well most of the time) when that trip is not really feasible for just a zipper.