Oil prices are down across the country, but economists say grocery bills are staying high because of a practice called ?sticky prices.?

Many food companies raised their prices when oil costs skyrocketed this summer. Though the price of a barrel of oil has come down 29 percent since July, the companies are charging the same for their products.

?It's not sticky,? Nassau Community College marketing professor Jack Mandel says. ?What it is, it's called selfish prices, because once they can get away with it, they can stay with it. And that's the problem."

Small businesses are also getting hit by the high food prices because they have to charge their customers more.