I've had this problem. Went into a store in another state looking for seltzer to make egg creams. Nada. Brought the rest of my purchases to the counter where the clerk asked if I had found everything I was looking for. I told him I hadn't as I was looking for seltzer (think r dropping south shore accent). He stated they had it, led me to the back by the refrigerated drinks and snacks, and proceeded to ask me, "Mild or spicy?"
As I started to say, "I wanted seltzer, not salsa," I cracked up and told him we just had a Seinfeld moment.