Here's my ? If a credit card is stolen and then used at a gas station by the thief, can the officer investigating the credit card fraud ask for the video survalnce from the gas station ? Or do they need a warrant to get that survalence?

They can ask... but officially I believe they do need a warrant. (but that is just a guess.. I am not positive)

Yes, the police can ask for the tapes and generally the store owner will provide them. But the store owner does have the right to require a warrant.