Bot prevention System:
It is not a matter of that they don't know what causes the woes of the D3 economy. It is a matter that they failed to stop them. It seems blizzard lost the war against botters and does not know how to stop them.
Botters and 3rd party is definitely to blame. And they are active every single day.
And yes, I do know how to stop botters. I know that sounds like a real bold statement and I don't expect you to believe me but it involves a system that targets accounts that act like bots with questions that only humans can answer. You must use unique questions each time so it will always be impossible to program what question will come next. You must also make sure 99+% of normal players will never even see this system because it is only targeting potential botters.
Step 1.) Any account that plays over 105 hours within a 1 week time frame gets flagged for a question. (99%+ of the popluation do not play this much)
Step 2.) The question is simple that anyone that can read their native language can answer but a bot wouldn't know what to do. For example "What is the 2nd word in this sentence?"
Step 3.) The correct answer exempts that account until another "105 hours played within 1 week" period occurs. An incorrect or missing answer flags the account for a Manual review by a Blizzard staff.
Step 4.) The Blizzard staff examines all the account activity and is the final judge on if to ban or not.
Now, I'm certain that this setup could be improved and optimized. For example, the amount of hours for step 1 could be increased or decreased. But what I have here is a great start and the foundation for bot prevention. You ultimately want an automated service to flag bots for a manual review so no false-positives occur and normal players will never be affected by that system. I also suggest flagging accounts who use several clients per IP address. The only ones using more than a couple clients per IP address are typically abusers.
In Theory, I concurr. In practise though mate, no chance. Botters to reviewers the numbers are against you from the start. Granted if you developed a fully automated system, maybe/could be. But these guys are so well embedded now into the fabric of the game, to route them out, unfortunately just isn't going to happen. And whilst the majority hate these little buggers, there are those that will support them (be it 3rd party gold sites etc). I think most you would get are the twits who don't know any different and use 3rd party software as a quick fix cheat. Same case scenario at the moment following Gold-gate. Scammers had an escape route planned, whilst the idiots thinkin they could make easy bucks, got caught napping and can now only profess their innocence.