No (at least they aren't supposed to based on their policy and signage). I have seen the door greeter stop people with pets, including dogs, in the cart from entering. There policy, at least as of 4-16-18, is "Costco does not permit any animals, including service animals to be placed inside a shopping cart." Service animals (not pets or emotional support animals), as in all businesses, are legally allowed into the store (but not in the carts) as is explained by a sign at the entrance.
And real service animals, not fake ones.
It says, service animals only
Posted at the entrance "Service animals only"
Service animals only
No
Yes they do
No, only service animals.
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