Why should I care? It's because this person is not making something work for him, or pulling off a stunt. That presupposes that what he's doing is legitimate but clever. It isn't. It's just downright dishonest.

People who bend or break the rules cause the airlines hassle and cost in tracking them and enforcing the rules. I'd rather the airlines had that money to spend on improving customer service or FF benefits or reducing fares - or even, at worst, improving the rewards to their shareholders. Anything's better than the waste.

Airlines will also tend to react by making ever more restrictive rules, which themselves tend to hurt those who abide by the rules as much as they curb those who bend or break them. I'd rather that the rules permitted more, because everyone abided by them and what they were supposed to mean and permit.

If you think that this is an overreaction, think what the airlines might do if too many people sold their miles in breach of the rules. One change might be restricting reward tickets to account holder only, or to immediate family members. (Some FF schemes already do this, so it's not that far fetched.)

Where would that leave rule-observing FFs who want to take a couple of friends on a free shopping trip? Why should we all suffer in those ways? I say we should definitely bust those who we find are doing this.