Look, the way the way the game economy works is there are generators and sinks (for both gold and resources). Resources are scarce (they can be exhausted) but replenish over time. An example of generator is a Sab mining spot, or mount spawn, or monster loot drops. Some sinks are building a keep, or the auction house 5% fee.
I don't think there's any argument to be made that the parcel delivery tasks shouldn't pay gold. Any resource generator can be converted to gold through trade and many monsters directly drop gold. I think the argument is that it should incorporate scarcity, or else is can be farmed indefinitely. The solution is to make parcel tasks a scarce resource that pays gold upon delivery. The amount of gold should be informed to the user before the task is taken on, and the gold reward depends on how many people are currently farming these tasks. The reward could change if you choose to deliver to a region that isn't heavily farmed. And the task reward replenishes over time as less people farm it.
I don't think there's any argument to be made that the parcel delivery tasks shouldn't pay gold. Any resource generator can be converted to gold through trade and many monsters directly drop gold. I think the argument is that it should incorporate scarcity, or else is can be farmed indefinitely. The solution is to make parcel tasks a scarce resource that pays gold upon delivery. The amount of gold should be informed to the user before the task is taken on, and the gold reward depends on how many people are currently farming these tasks. The reward could change if you choose to deliver to a region that isn't heavily farmed. And the task reward replenishes over time as less people farm it.