Reminds me of these stories:
1. Back in the day, I used to churn credit card points via the ATO. I just overpayed my income tax account and asked for a refund of the excess amount (by the way you can do this). Did it a few times (churned a few hundred thousand lol), and then some guy from the ATO called up and asked what I was doing. Told him exactly what I was doing (for points) and he told me I could only do it that once and not to do it again. Then I did it again, and he ended up reversing the transaction back to my credit card. See I don't know why he had to interfere. From my perspective, I was not breaking any laws, and I was using perfectly legitimate means, within the rules, that the ATO had set up to achieve my aims. ATO was not making a loss. But no, an overzealous bureaucrat had to interfere, for no apparent (and legal) reason. In fact, I think his method of refund, was not within the rules of the ATO at the time (i.e. only bank transfer or cheque allowed and not credit card)
2. Or I was recently selling discounted wish gift cards on ozbargain at a good discount with many happy customers. Then the mods decide to shut it down because the "classified ad system was not designed for such a thing". Stupid decision really.