Nah, that's the infamous "Bubba Move". "I don't know - it just doesn't work right" or "It slips" or whatever - slightly vague but simple explainations with no appearance that you understand what's going on(or very slightly/newbie level understanding). Also works well at Frys or other places when you have to make a return.
Osh is better because they are a reseller. So for them, it's not worth their time to deal with it. Stick it in the returns bin to be shipped off at the end of the month to Sears. DEal with the next customer. They 99% of the time handle it like any other defective product(barring obvious things like snapped in half or half melted/etc).
I think you are getting a half baked employee that just don't care.
