Uh-huh. So is the "We don't carry that" line when the clerk is just too damn lazy to find out where the item is when asked. I've heard it enough times to recognize when a clerk is about to trot it out - so when an employee in a craft store had no idea what metallic goldfingering was, let alone where to find it in the store (it wasn't where they'd had it the previous times I'd bought it there), and was rolling out the list of excuses, I interrupted her and said, "And don't even think of telling me you never carried it here, because this is where I bought it less than 6 months ago." Funny, how fast she closed her mouth. I ended up getting it elsewhere.
And then there are the ones who seem to really want the customer to go somewhere else. My dad and I went to Walmart to look at computer desks (to measure, to see if it would fit into the room). I asked the greeter where they were, and he said, "Oh, we don't have those here. You have to go to the big cities like Edmonton." (I live in the 3rd-largest city in my province). My dad was about to leave, but I told him, "I know they have them, let's just go find them." So we did, I wrote down the measurements, and on our way out, as the greeter was talking to other customers, I waved my notebook in his face. "Here are the measurements I took of the computer desk you told me you don't have."
The most recent incident was a couple of years ago, when I decided to get a Discman (like a Walkman, but it plays CDs; seems odd to have to explain that, but apparently the younger generation doesn't know about these things). An online search turned up two local possibilities, and I decided to go to the closer one. When I asked the clerk to tell me where to find it, she looked blank. "Oh, we don't have those. They haven't made those for like 20 years. You better go to a pawn shop."
So I told her that this was very interesting - considering I'd seen them advertised on the store website the previous evening. I ended up getting it from the other place - much farther away, but online ordering worked with no hassles, and it arrived several days faster than expected.
I don't mind if an employee can't remember every item the store carries - but don't tell the customer "we never carried that" or "go somewhere else" as a first response. Clerks should be taught that if they don't know the answer, an appropriate response to the customer would be "I'm not sure, but I'll try to find out for you."