I think we're all in agreement that something needs to be done, but the ethics of disrupting a business's capacity for staying in business is shaky ground.
Imagine... a large car rental place in your city rents out cars on the cheap. They're all identical, impossible to tell apart visually. They have very lax security on them, a basic door lock that's easily broken into without damage, no car alarm.
A criminal gang in the city has started targeting these cars, they're being stolen frequently, used as getaway cars for store robberies and even an occasional bank heist. Security foortage is worthless because all the cars look alike. The thieves apparently have realized if they just dump the cars off where they stole them after they're done without really damaging them, nobody cares. Not the rental place, not the customers. The criminals are impossible to identify or prossicute.
The mayer however is getting pissed off that the rental company is refusing to take any action. The rental co simply does not care, because it's not hurting them or upsetting their customers. Why should they spend money to fix someone else's problem?
What does the mayer do about it? What can he do about it?
This is the botnet problem. So, approach it from that perspective.
The rental co already has a few policies in place. They have monitoring software in the car that is used exclusively to watch for road-rage or dangerous driving. If a customer is driving recklessly and risks damaging the car, they may get a warning from the rental co, or even have their rental remotely disabled for a few days. (copyright DMCA letter anyone?)
So.... since they already have this monitoring system in place, and should already be able to tell when a car is stolen and being used in a robbery.... the mayer forces the rental company to use this information to help curb the problem of their cars being used for public harm.
This is how it would work in any other arena. So why does no one take action against the botnets? Does the rental company's right to run their business like they want to outweigh the serious problem they are facillitating? Of course not.