Not trying to push, or be too political here, but why would that bother you with Walmart?
Granted, taking a Wii into a Walmart is, as others have mentioned, just asking for a problem. They're tight on shoplifting and would assume you stole it.
In this case though, it's been proven in several studies that Walmart only is able to stay in business due to it's employees reliance on government assistance. Their FTE and PTEs need food stamps, medicare, etc. If they paid a living wage to their employees they'd still be profitable, just less so, and taxpayers wouldn't need to subsidize them.
So, man, that's the LAST company on the planet I'd feel guilty about testing a device at.
Doesn't cost them a thing regardless. So even if you disagree with the tax subsidy issue it doesn't cost them business, or employee time for you to test something there. Not sure how you'd be taking advantage of them in that case. Worst case spend $2 and buy a bag of chips on the way out.....
Because I own a business and I would be highly pissed if someone did that in my store. Low wages don't matter to me. People don't have to work there if they don't want to.