If they are infrequent flyers, check the expiration times.

If they live where they can fly on AS metal, they may find that AS' 10,000 mile one way award coach flights are more within reach of occasional flying than other airlines' 25,000 mile round trip award coach flights.

Another possibility is to check to see if any of the airlines' miles are spendable on magazine subscriptions or other things that they or you might use.