Originally Posted by corporate-wage-slave

In at least some scenarios there would be some sort of refund for cancelling your ticket before a departure you are not going to make, even if it's just a refund of taxes. Also generally speaking it would be even better value for money to defer the next sectors for a future date in the next 12 months after the first flight is flown, and if you look carefully there may be no fare difference either given it's on a historical pricing basis. Even tickets which are non-refundable often have relatively good rebook options. A good read of the fare basis will tell you if either approach is worth doing.

The comment about no-show fees above could be valid here since occasionally there are differential rates for refunds which would be deducted from any payment.