Not that I'm a huge fan of Wal-Mart at all, but read the fine print on this article. He wasn't banned for the price-match policy at all --- he was banned for physically threatening a sales clerk, pure and simple.
And if anybody gives a crap, there's a long-winded debate in a very obscure rasslin' board dating back almost a decade that claims that this Joe Cantrell, a former California wrestler, has been guilty of every kind of con game under the sun over the years. I won't even post the link unless anybody even gives a rat's ass.
I hate Wally World as much as the next guy, but the bottom line on this story is that a pro con artist probably got exactly what was coming to him after he tried to bully his way through a sales clerk.