Ferrets are NOT LEGAL to own as pets in California and Hawaii. This is why you Will Not find for sale at Petco or any other legally operated pet store. I am surprised that store staff were not able to explain this during your visit to the store.
1st I don't know if they are leagal in this state I could be wrong, 2nd you should check online and see but I believe no Petco whould have one.
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