Last week we mentioned that Costco has a habit of backdating the starting date for lapsed membership renewals, which prompted Monica to write in and let us know of another issue they seem to have with billing. If you renew your executive membership with Costco but then apply for the Costco American Express card, Amex will charge you the membership fee a second time. Monica says the Amex CSR who fixed the problem told her it happens all the time.