Of course, the HA are keen barterers. I want your bowl, you want my eggs, we do a deal whereby I get the bowl for an agreed number of eggs. Simple. Well, yes, but it's not actually how most of the transactions among the HA get done. Instead of physical coinage, the HA employ a system of favours. If you want someone else to perform a service for you or to provide you with some goods, but you don't have anything to hand with which to bargain, you offer them a number of favours. These can later be cashed in when your circumstances change (eg. when the whisky you are distilling is ready, or when your goat has kids, or when your cold gets better). Most of the time, however, they're traded. This can lead to conversations which seem amazingly convoluted to the uninitiated.
"Well I'll patch your roof, but it'll cost you three favours."
"Right, so I owe you 28 now."
"Well I owe HAK 18, so you can owe me ten and HAK 18, and tell him I'm square."
"Tell him yourself, and since he owes me 5 I'll only owe him 13."
"Well, whoever sees him first can tell him."
There are two things to note about this system. Firstly, it depends very much on honesty: if one HA lied to another HA, they would basically be manufacturing credit for themselves, thereby increasing the money supply drastically, potentially leading to rampant inflation. Secondly, every favour is equal: a favour from Lakka, the chief, might well get more done than a favour from some bloke who collects firewood, but they cancel out on a one-for-one basis (not that Lakka gives out favours of his own very often, the skinflint).
Of course, this system also means people need to have bank books for memories and adding machines for brains... Nevertheless, it works. The first issue (why don't people cheat) is addressed by cultural practices which greatly discourage any such actions (death by having your head stomped on), and by the general honesty the HA seem to have even when practically destitute (which is their normal state of existence). The second issue just isn't an issue: what you get for a favour from Lakka might take him less time to perform than what you get from the woman who suckles babies, but its worth is equivalent6.
When a HA tries to cash in a favour, it is not incumbent upon the favour-giver to do what is asked; it's an option. Most will do it, but, as I'd noticed before, they don't like the idea that they have to do it; they're likely to exchange the favour being cashed in for another one owed them by someone else if they can and they're feeling moderately stroppy.
Now if you consider that there's a whole society of people operating this favour system, it almost beggars belief that people can memorise so many numbers without making the kind of mistakes that would result in their getting a head stomping. The way it tends to work, though, is that people will try to collect favours belonging to certain individuals, so if you have 30 favours from orc X and are offered 15 favours from orc Y, you might ask for them in X favours if they're available, rather than in Y's own. Using this system, most orcs only need keep tabs of around 10 principal accounts, with perhaps a pool of 10 or more others at any one time (but less for a while if someone drops dead and you can't cash in their favours any more).
