Satirist Bill Maher is the latest celebrity to call foul on Costco Wholesale (COST) for not following up on its 2007 pledge to stop selling eggs from hens kept in so-called battery cages.

In an Op-Ed in The New York Times titled "Free the Hens, Costco!", the host of HBO's "Real Time With Bill Maher" wrote of how a life spent entirely in a 9-inch-by-9-inch cage with four or more other hens is torment for the animals.

"The animals' muscles and bones waste away from lack of use, just as yours would if you were unable to move around for two years," wrote Maher, who added that multiple probes into the cages found "animals with deteriorated spinal cords, some who have become paralyzed and then mummified in their cages."

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The fact that Californians voted to ban the cages in 2008 is evidence that many consumers don't want the cages, a position Costco had said it agreed with the prior year, Maher wrote.

"Almost 10 years later, the company has yet to release a timeline," Maher added. "A company that takes pride in its other socially conscious positions can do better than this."

Costco did not return CBS MoneyWatch requests for comment.

Maher's appeal comes three weeks after Ryan Gosling became the first celebrity to join a campaign by the Humane Society of the United States to convince Costco Wholesale to switch to cage-free eggs.

Sen. Richard Blumenthal, D-Connecticut, a ranking member of the Senate Commerce Subcommittee on Consumer Protection, has also recently called on Costco to halt the practice. Blumenthal cited the increased risk of salmonella outbreaks by what he called "inhumane and unhealthy practices."

On Tuesday, General Mills (GIS) followed similar pledges from corporations including Wal-Mart Stores (WMT), Kellogg (K) and Starbucks (SBUX), and committed to using 100 percent cage-free eggs as part of the Minneapolis-based food processor's plan to improve its animal welfare standards.

"It's the right thing to do from an animal-welfare perspective, and consumers want to know where all their food is coming from -- how it was cared for and treated for its entire lifespan," Steve Peterson, the company's director of sustainable sourcing, told CBS MoneyWatch. "We're not the first to do this, and we're obviously not the last."