That is why I always look for the price per unit that is usually found on the tag in the corner. If I can't find it on the tag, I pull out my cell phone's calculator and figure out the price per unit. It's a great money saving activity.
Only time I've ever encountered items in Walmart ending in $.00 was when they were on sale. It seems to me that the individual units are on clearance sale, and the two packs are just on promotional pricing. At full price, the two pack would be cheaper than buying two individual deodorant sticks.
Promotion, end-stand merchandising, any sales, DOES NOT warranty a better price ; keep your eyes open dear consumer, and please come again! :D