I would like to put in my two cents on how not to get caught;
1. Mourning: A bad event is well... a bad event. If your prized Maraquan Draik is zapped by Boochi, a "regular" user wouldn't just keep hitting refresh in a shop. A mourning period is (according to some studies) of 7 minutes for something that has little intrinsic value such as a virtual pet. If you have the Remote Control enabled, try to keep an eye on it and maybe stop for a few minutes as if you were in shock. This adds a tint of humanity to your Auto Buying.
2. Schedule: Some members do Auto Buy overnight and I can not stress the fact of having a "rest" period. There is a "rest" period for when you buy something over (I believe) 250K already pre-installed in ABrosia. I would recommend a 2 or 3 hour period in which you would schedule a stop in ABrosia.
3. Neoboards: In order to make an account seem more legitimate, the Neoboards can help add to the illusion. Even just a silly post over what petpet is the best can make your account more believable.
I can think of some other things over time, but this is what I think adds more depth to an account using ABrosia.