I shall preface this post by stating that, once upon a time, I was a tech salesperson. I learned two lessons very fast. The first was to NEVER underestimate the customer. The second was that a customer looked at a product for a reason. It was my job to help them decide whether the product was right for them. Sometimes their mind was made up and I just had to ask if they needed any batteries to go along with it.
Actually, there was a third thing. NEVER throw out a line of B.S. so thick they'd have to step through it to get out of the store. If I didn't know the answer to a question, I wasn't afraid to say so. And I ALWAYS offered to find out the answer if it was in my power to do so. Often it simply meant digging up the manual for a display item.
Imagine my total lack of surprise to encounter a salesperson who violated all three lessons.
UPDATE: Today I found someone who knew what they were talking about. The age of miracles has not passed. My only problem was that there were so many people looking at the item that I didn't really get to see it. Oh, well. That's not really a complaint.