Nepal is the seventh poorest country in the world and tourism is the main stay of the economy. Income and aid is unequally distributed and the trekking industry in particular allows for some of that money to flow into remote places and poor farmers' pockets. Jobs as trekking porters are highly sought after because they provide much needed cash at a time when work on the farm is at a standstill. On the trekking porter's list of concerns cash comes first, then safety.
The worst aspects of porter pay are that the sirdar (porters' manager) will often take an excessive cut for himself, and that individual trekkers, or cut price trekking companies, will pay too little. It often happens that a porter will have little or nothing left after food and shelter has been paid for from his wages.
Weight of load is pretty standard and is set by law in Nepal. Sometimes porters ask for double loads in order to earn more. Sometimes a sick porter's load has to be distributed between the remaining ones and they are paid more to carry that extra bit.
However, IPPG would encourage trekkers not to overload porters especially the young or the old.
The main point is that if a porter dies or is injured and is unable to work, it is a disaster for his dependants in a country with no safety net.
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