I would probably have said something if I noticed the problem, but I would more likely be focused on my purchase and trying to decide how much of each fabric to buy. Don't beat yourself up because you didn't speak up; she will just come in and buy some more to complete the project. Or maybe she was making cafe curtains and they would start half-way down the window, or perhaps she had another fabric that would be combined with what she bought. I no longer expect the person in JoAnn's or other chain stores doing the cutting to have any knowledge about sewing, although it's a pleasant surprise if she does. Sometimes I'm asked what I'm making and I say I'm just adding to my stash. Sometimes the look I get tells me I might as well be speaking Greek.