Of course the point of spending money is to signal your need.
Now my question to you is:
Does everyone have money? If not, how are the people without money going to get their share?
Do they have different amounts of money?
If so, and the ‘richest’ is greedy and can commandeer all the fish and coconuts (that can be collected) by spending all his money, are you happy that the rest go without, or if not everyone, at least some?
To make a market, we have to assume there are different sellers with different abilities. And also buyers that can neither catch fish nor collect coconuts. Otherwise you just have a collective of people working together to collect the food they need (a bit socialist :) ).
We also need to assume that catching fish takes longer and requires more skill than collecting coconuts and that it takes no time to learn coconut collecting but years to become a good fisherman — if demand requires a shift in the amount of one or other commodity, pushing up the price of the commodity in short supply.
And there also needs to be competing sellers that together cannot supply all demands (otherwise there is no market… people just say what they want and it gets supplied) and that some buyers want only fish and others only coconuts, while still others want both, or more of one than the other.
We could also assume that everyone could have enough to live on if the food was shared equally, with some having to eat food they don’t like.
With all these different needs and ability to supply…
How do you see it working?
Please explain in an actual example using your money allocation process with actual numbers