The Walmart in My town used to do the same thing. In general stocking is done over night. However, when this ammo scare went down...they made the department decision to stock at 7pm to sell it when it came in. they are probably adhering to a store policy and expecting that you will take them at their word. Reason #152 that I have been giving LGS's my money instead of Walmart!
“The beauty of the Second Amendment is that it will not be needed until they try to take it.”
― Thomas Jefferson
“The constitution shall never be construed...to prevent the people of the United States who are peaceable citizens from keeping their own arms.”
― Alexander Hamilton