Best Buy Refuse to Sell to Chinese Visitor

I had a few chinese visitor last month. All of them want to buy Apple IPad. But when they went to local Best Buy, store manager refused to sell more than one to the group. Her reason was that they obviously come from the same group, and she can only sell one per person. Even though they reserved 2 IPad by phone, they end up with only one that day. I already complained this to Best Buy head quarter, but there is no progress on that complaint. Is there anything I can do on this? I am in Texas.

Thanks in advance for all your help!