Well, there may be some truth to this, depending on how exactly you were meaning it.
Kershaw DOES sell some lower quality knives, that are frequently sold by places like walmart. You seem them often around holidays, and they are usually a cheaper versions of other production models (manual instead of speedsafe, etc), and are bundled with like a flashlight, or something else for like $20. However, I doubt the quality control is worse (unless they're made at factories that kershaw normally doesn't use or something like that). The materials (blade steels at the very least) are lower quality (3Cr13Mov, etc).
So, I doubt that for any given model, that there is a significant difference in the build quality whether it is sold by a big box store, or a small shop (assuming of course that the small shop doesn't inspect/return merchandise before they hit the shelves). There is a chance that you will find lower quality models sold at big box stores though, but again, IIRC, they are totally different models, not just "worse" versions of a normal model.
Hopefully that makes sense

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