Try asking someone who works in electronics if they have any available. Sometimes they have them stashed in the back to portion them out to people on their terms. I know my local Target has signage that says 'only one pack per customer' for amiibos and Pokemon cards and such and you need to ask an employee to fetch one for you. Haven't been to a Walmart recently to know their policy, but I imagine it's similar. If the employees don't know, it's possible they just don't have them in stock period.