Do note that whilst Expedia do not charge a credit card fee, they do include a fee in their quoted prices which renders them more expensive than the equivalents sold at ba.com.

In addition, a number of other websites are currently corrupting price comparison sites by attaching a 'discount' to their published fares, and then subsequently (beyond the point where the comparison bot reads from) adding on a 'service fee' and then a credit card fee.

Whilst I agree that the OP's experience is entirely unacceptable (and I am quite sure that Dilly will be able to assist), it is in BA's own interest to ensure that it is indeed the cheapest place to book its own flights, as it will have no commission payments to a third party to cover when it deals directly with the passenger.

The situation should, therefore, be mutually beneficial for carrier and passenger.