Yeah, I get that. But it turns out that they're wrong. Are you suggesting that shippers try not to break things purely out of courtesy? Maybe, but I think incentives aren't aligned such that that can go a long way. With no other feedback, they want to get their job done quickly so that they can move on to the next, and get paid for moving more things.
If they're doing this purely out of courtesy, then yes, I could understand that being wrong about the fragility of bicycles could lead to such a disparity of broken things, since they pay no consequences for being wrong. However if there is a simple insurance policy, which I can only imagine any business would have with a shipping company, they are paying consequences for it, and they would have reason to learn, and try to treat bicycles a little more like televisions.
Apparently this isn't happening, but I don't understand why.
EDIT: I would add that the only explanation I have is that bicycles are less expensive than televisions. This implies that putting a television on the box leads the shipping company to believe that they have to put more time (aka money) into care for the box than they actually have to. This is what lead to my comment about fraud.