I'm not sure why you are continuing because it's impossible to defend against all Sybil attacks in an open network.
>If your counter-point to that is that users will waste money then clearly this attack is not sustainable
One simple scenario where it is sustainable is when you are a part of a competitor's network where the existence of the other network results you in making less money. If the attacker wants to destroy the other network to gain market share they may be willing to have a budget they spend each month to attack it.
>And if your concern is so extreme that a whole network around a user is locked down
It's not extreme if there is to defense to it.
>it would take a lot of work to even get into one of these states
As I mentioned it is easy to run multiple instances of the software to become the majority of the network.
>The same way it's unlikely you will keep buying bread from the guy that charges twice the market rate.
If you check 100 stores in your area and they all charge that rate you may think that's the market rate.
>If your counter-point to that is that users will waste money then clearly this attack is not sustainable
One simple scenario where it is sustainable is when you are a part of a competitor's network where the existence of the other network results you in making less money. If the attacker wants to destroy the other network to gain market share they may be willing to have a budget they spend each month to attack it.
>And if your concern is so extreme that a whole network around a user is locked down
It's not extreme if there is to defense to it.
>it would take a lot of work to even get into one of these states
As I mentioned it is easy to run multiple instances of the software to become the majority of the network.
>The same way it's unlikely you will keep buying bread from the guy that charges twice the market rate.
If you check 100 stores in your area and they all charge that rate you may think that's the market rate.