I don't believe it works that way..... Walmart would have to activate the phone for you before they can sell it to you at the subsidized price. Otherwise, what is to stop people from buying as many subsidized phones as they can just by showing the Walmart employee that you qualify ?
And since Walmart does carrt AT&T phones, they have the ability to check your availability.
And since Walmart does carrt AT&T phones, they have the ability to check your availability.
Just look on AT&T's web site. If it says you're eligible there, then Walmart can give it to you at the subsidized price.