I have so many and have stoped travelling. I have had a few trips, business class around the world on frequent flyer points which means I spend an awful lot!
However it is wonderful getting these flights for nothing -I don't often use them for Australian flights as they seem to be so cheap I don't think it is worth it unless you do not travel overseas.
Oh! Finy.......you don't 'get these flights for nothing'!
You've spent 1000's of $$$$ to accrue those points, probably more than what the cost of just outright buying an airfare!
Then there're the various Taxes to be paid, which amount to many $100's!
Same as there's no such thing as a 'free lunch', there's no such thing as a 'free airfare'!