You are likely to travel to at least one of the destinations serviced by Worldwide Airlines. Some of the destinations to which you would be likely to travel are serviced by airlines that compete with Worldwide Airlines. The purchases you normally make are invariably from businesses that accept the X card. You can accumulate an amount of credit with Worldwide Airlines that is at least as great as the value of any of the potential purchases you could not afford before.
Advertisement: Every time you use your X card to charge any purchase, you accumulate credit with Worldwide Airlines in proportion to the cost of the purchase. This credit can then be used to reduce the cost of your Worldwide Airlines tickets. So with this new program you can now afford purchases you couldn' t afford before: the extra money you can save on travel is money you can spend on these purchases!
The advertisement's argument depends on assuming which one of the following?