Yeah, everyone in sales has his list of sentences he is sick of hearing.
And of course we all have our most stupid customer. The really sad thing is even that get's topped.
Mine?
I was working at the largest newsstand in town. In some cases we had magazines about something in different languages. And in came this guy (I refuse to even call him a potential customer).

Guy: "Which monthly magazines do you carry?"
Me: "About what theme?"
Guy: "What themes do you have?"

The largest newsstand in town. I don't think there is a theme it doesn't offer and as I said, some we had in different languages. I could see the unbelieving looks of other customers standing behind him.

Walk in the door "What's on sale?"

No hello, how are you? or pointless discussions about the weather. If there is no sale we get "I'll be back."

At m last job I got a good at spotting the "I'll be backs" when they just entered the store before one word was spoken.
But yes.

This is the same person who would ask the waitress what's on a bacon, lettuce, and tomato sandwich.

Oh yes, I have a frien...er...acquaintance like that, only she wants to know what kind of bacon, lettuce & tomato are in the sandwich. I was on a non-profit board with her and the other board members hated going to luncheons or dinners with her. The sad part of it is that she's intelligent, knowledgeable, and well spoken...but, well, just plain weird.

When I worked at Radio Shark my manager sold a TRS-80 Color Computer to a customer he knew would return it. I was working the morning the customer brought it back -- and as the store's resident geek, I was silly enough to ask what was wrong with the machine. The customer knew all about computers. After all, he had seen people use them on Star Trek. He just didn't realize that one had to be able to read.

I say "your sh***ing me" but some folks who know how to read, don't.

There are more than two dozen people on my street. I think it's safe to say that the number of them who are functionally illiterate is close to/over a dozen.

I repair ATM's for a living. I'm sick of "Any free samples?"

Every occupation has to tolerate those "gems." I wish I could remember the ones from my 40 year career, but after being "retired" from it almost 10 years, I, mercifully, can't remember any of them!! LOL