There’s a mutation, fairly common in northern Europeans, in which homozygotes absorb too much iron. Untreated, iron accumulation can lead to cirrhosis and a form of diabetes. Treatment is simple: bleed the guy, early and often. It’s one of the few syndromes where old-fashioned medical treatment actually worked – purely by coincidence, of course.
Obvious question: what do you do with all that blood? Obvious answer: After meeting the needs of the creatures of the night, use whatever’s left over for transfusions.
But, in the US and most of Europe, we generally don’t, because we’re nuts.
Ya see, the Red Cross has a policy: donors are not to be compensated, other than orange juice and cookies. Since these guys (mostly guys, of course, although perhaps that will change now that everyone and his brother can menstruate) need to be bled, giving blood to the Red Cross would allow them to avoid paying some MD to drain them and pour it down the sink – so, they would in effect be receiving something of value.
I’d like to think that the true motive for this policy is protecting medicos’ income stream – but, you know, their stated reason is stupid enough to be the real one.