I have said before how weird it is that so many customers don't think their furniture purchases will fit in their huge cars/vehicles/SUVS. The weirdness turns to annoyance when
1) they won't measure items. Somehow they think eyeballing it will do, even as they express doubt that it will fit.
"I think this will fit in the back of my car. Can you carry it out for me?" [I find people to carry it out. They gird themselves for the lift. The customer returns.] "You know what, I don't know if it's going to fit!" And then we don't even get to try.
2) they don't even begin to trust me when I suggest that it probably will fit in their car, regardless of my relatively good spatial skills (which, to be fair, they probably don't know I have) and the fact that I am at the store all day, measuring shit and helping people with the exact same scenario.
I don't know about other clerks, but I'm not even going to suggest shoving something in your car unless I'm pretty damn sure it will fit.