WASHINGTON, July 4 -- For two and a half years, American grocery shoppers paid elevated prices for one of the most basic items in their kitchens, as egg costs climbed to record highs that the federal government now alleges were not entirely the product of avian flu devastation. Three of the nation's largest egg producers, the Justice Department announced last week, had been coordinating their bids to influence the price index that grocery chains and restaurants use to set what consumers pay at the shelf.

The settlement they reached, $3.3 million in combined payments and a donation of 53 million eggs to food banks, has already drawn sharp criticism for what it does not give back.

"This isn't making it right for consumers," said Angela Hu...