I called WalMart and talked with the customer care department and she searched and read me this.
"There is no policy against customers carrying their handgun in our stores as long as he/she is legally permitted by their state to carry the handgun.
As a private property owner, Walmart has the authority to ask customers to remove their handgun or leave the store on a case-by-case basis if customers or Walmart associates express concerns about the handgun.
Walmart Customer Care"
She did say that it has to be some kind of store management that asks you to leave not just any employee can tell you to. As i have read most of the time they just ask you to remove your firearm and place it in your vehicle before returning into the store.