Ernest likes to eat pistachios. He’s also a good consumer, checking unit prices and choosing the store brand of his favorite snack. When he picked up a bag at his local Walmart recently, he noticed that something was missing. About four ounces of pistachios, in fact.

The nuts sell for $6.98 per pound in the generic variety, sold in one-pound bags. Simple enough. The price was still $6.98, and the shelf still posted the unit price as 43.6¢ per pound, but Ernest knew this couldn’t be accurate. The new bag only had 12 ounces.

He did what we would recommend in this situation: took the bag over to an employee and asked for the bag to be scanned. The price for the new, shrunken bag? $6.98. The price per ounce is then 58¢.

“This is more expensive that the national brand, which is sold for about 55 cents an ounce,” Ernest wrote to Consumerist. “Maybe they hoped no one would notice.” Maybe. They might not, as long as someone fixes that incorrect shelf tag: good idea to let someone at the store about it. If the wrong sign is still there next time, flag down a manager, or contact your attorney general’s consumer protection office.

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