There can be quite a bit of noise and commotion in a pet store especially when a new shipment arrives or when there is a sale going on and in comes a couple of families with their children and friends. Many pet stores have a separate little room aside from the main part of the sales floor that customers can see into but not get at the birds. In stores like these the birds are not kept very long before they are gone, and we can only speculate as to how much an individual bird is affected by this experience. We do sometimes hear stories of birds that are so stressed by it that they are placed on various anti anxiety medications. But even then we don't hear enough to have anymore than a glimpse of the full effects of these situations. We only know that the experience is very bad for the birds. This is not to say that they can't handle a certain amount of stress, because to varying degrees they can.
It could be likened to post traumatic stress disorder in the troops who go to war. Even though they are trained to handle the stress a certain number of those who return will never again be mentally and emotionally stable or safe to be around. Some of them will be fine with enough therapy.
Greys are sensitive to the effects of stress, and if they stress over much then they may pluck their feathers out, or they may mutilate themselves, or they may become aggressive towards humans and other living things.
To answer your question of what is the difference, I submit that the only difference is that due to the fact that the birds are taken in hundreds of different direction and that there is no place to report this to or even that keeps a record on it, you the private individual just do not hear about it very often.
The Grey that Pajarita describes to you in her last reply could very easily be my Grey on any given day right now with the single exception that Kookooloo has not quit most of her plucking yet. She has made a lot of progress since I got her, but we still have a way to go.






