Once we understand the hocus pocus behind these schemes we can understand how to make them work for us.
Stuff to buy in Oxford.
I am presently forced to live on chocolate truffles and champagne. The truffles are good but I am not that keen on champagne- and the fact that I am not a natural drinker of champagne makes me the ideal person for a free bottle and the fact I do not take many trips by air makes me a candidate for free flights!
If I liked champagne more I would have to pay for it!
Economics is full of such ironies.