Don't worry about your iOS passcodes, worry about your credit card PINs. The new chip-and-PIN standard coming to the US puts all responsibility for unauthorized purchases on the cardholder, and this underscores how easy it is for a thief to learn your PIN.
Federal law protects credit card users from unauthorized purchases, and provides lesser protections to debit card users. I can't see how using chip and pin would change anything.
https://www.consumer.ftc.gov/articles/0213-lost-or-stolen-credit-atm-and-debit-cards