For me personally it would have to be lack of product. More so stores moving old waves out slowly & bringing in the next wave seems to take too long.
Also another pet peeve of mine is people taking too long in the cashiers line especially @ Walmart. Some people go into the express lane with far too many items meanwhile I usually only have 1-2 items.
Would like to hear from all of you about what annoys you most about big box retailers ?