That's shockingly stupid. I also worked for a major Walmart IT services vendor in another life, and we always had to be careful about how we handled them, because they didn't always show a lot of respect for vendors.
On another note, thanks for building some awesome stuff -- walmart.com is awesome. I have both Prime and whatever-they're-currently-calling Walmart's version and I love that Walmart doesn't appear to mix SKU's together in the same bin which seems to cause counterfeiting fraud at Amazon.