We love their organic corn chips. They taste good, the price is competitive with name-brand chips in the regular grocery, and they don't go stale too quickly (if we're careful about closing the bag) which is important because of course we don't eat chips constantly, only when we have chili! After reading in
The Omnivore's Dilemma about the chemicals dumped on conventional corn, I want to avoid it as much as possible!
Costco also has eco-friendly dish and laundry detergents made from plants. I have tried a lot of brands of those, and theirs isn't the most fantastic ever, but it is completely adequate, and the price is great!
About Costco vs. Sam's, I have read that Costco is one of the best employers among retailers: good wages, good benefits, respectful treatment of employees. I know someone who works there and raves about it. Whereas Sam's+Walmart has a long history of terrible working conditions, lobbying against employee protection laws, and hiring illegal immigrants and then locking them in the building and calling the authorities on them.

Also, I have relatives who often buy gifts for me at Sam's, and I've been very unimpressed with the quality.
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