One point, the fisherman doesn't keep raking in the money until it runs out entirely, it gets thinner and thinner, he ends up with (ex.) 99% and 1% remains in circulation, the economy is broken (he has many times more "value" than the entire state) but it can continue to function and the breakage may not even be noticed.
Let us think for a moment about that. How could the fisherman rake in 99% of the money ?
Imagine that everybody, except the fishermen, are putting all of their monetary possessions in circulation (otherwise it is already impossible to rake in 99% of the money).
Now, in order for the fishermen to obtain 1% of all the money, they have to produce *net* 1% of the entire economic value (net, that is, what they produce, minus what they consume).
In order to obtain the second 1% of all the money, due to deflation, they have to produce *net* 1/99 of the entire economic value.
In order to obtain the third 1% of all the money, they have to produce *net* 1/98 of the entire economic value.
And so on.
In order to obtain 99% of all the money, they have hence to produce net:
(1/100 + 1/99 + 1/98 + 1/97 ... + 1/2 + 1/1) of all the produced value of all the others. This sum is even not right because between 2% of the money in circulation, and 1% of the money in circulation there will be deflation too.
But nevertheless, the sum is about 5.2. It means that the fishermen, by themselves, have NET produced 5.2 times all of the economic value that all the others have ever produced and consumed. So you might even think that to be honest they should have 520 % of all the money :-) but they only have 99% of the money.
Imagine this:
Joe, Bill, Jack, and Alice each have 25 Klonks (unit of money).
If Joe does something for Bill that Bill pays with all of its money, then Joe will now have 50 Klonks. If Joe does something for Jack that Jacks pays with all of his money, then Joe will end up having 75 Klonks. If Joe does something for Alice that she pays with all of her money, then Joe will end up 100% of all the money.
That's normal, because Joe has been doing EVERYTHING ! If you like the "debt" wording of money: Joe has now all the IOU because indeed, everybody owes him stuff, and he owes nobody anything.
Would you find it normal that after Joe has done everything, that people can still again ask Joe to do stuff ? Isn't it normal that Joe can now profit from the others without any return ? So it is normal that Joe has all the money in a sense. The "economy is not broken". Joe has just been giving a lot !
So on the "morality side" there's no problem for Joe to hold all the money.
In the same way, there's no problem for the fishermen to hold 99% of all the money if they have done NET 5 times more than all the others together.
However, money is NOT an IOU. Money is speculative. So the fishermen have a big problem. They have by themselves produced net 5 times more than the entire economy. They have been giving to the others more than 5 times the entire economy. They obtained against that 99% of the money stash (which, when spent again, will buy them of course 5 times the economy).
1% of that money is still circulating (or is hoarded by others, who knows !).
If the others put into circulation another monetary item, then our fishermen may just as well be sitting on a stash of assets which isn't buying anything anymore !