[Tenney]

I would imagine you can do "sealed box method", "item not in the package" (but that would depend on the item, more specifically the weight), you can claim that it is defective online after the fact and box them as well.
I would imagine many of the regular methods would likely work apart from the obvious ones such as DNA.

All that is my theoretical thinking. I have not done what you are attempting so take it as such.

I'm curious if they would actually have it in a box. They would have to ship it to one of their locations since they did not have it in the store at the time so it'd obviously be shipped, but if it is just the item itself that is handed to me I feel as though this ruins both of those methods. Defective online after would lead me to think a standard return/exchange would be offered in store. I'm not sure, so I'm hoping someone with some experience in doing the in store pickup would chime in if they see this.