You do realize that's two additional weeks of revenue for goldfarmers?
Especially because they no longer have to worry less about any account being banned, they can resort to extremely aggresive farming strats to make more gold/h.
If they got too cocky and all of their accounts get banned in Classic, they have to level those again, which leads to days without any income.
With the boost, you will always have bots at the ready to farm, they'll be back on day one even after the most brutal ban waves because unless Blizzard charges an outrageous amount for the boost, every bot will break even within days.
It also makes the detection of those network far more difficult, if you have botaccount that perma boosts all other bot accounts in Classic, you can easily link one of those bots back those others once you detect one of them, you can ban the entire network of a goldfarmer in one fell swoop.
With the boost, it's virtually impossible, because every bot is an individual.
It's basic business, really, you invest more but receive revenue sooner, which is crucial when a bot only has limited lifespan until the next banwave anyway.