I asked the same question when they sent me all the paperwork for the medical. They wanted all this completed at my cost BEFORE it would be sent to the Executive Review Board for consideration. I couldn't believe it. But they said I had to spend it to be considered, so I was left with no choice. What woukd have got me alot more annoyed is if I was unsuccessful.
They even had to cheek to say if you do not complete the medical we can can withdraw your application.
Further investigation uncovered that the information the company was looking for was for issues years down the track. Although I already held a Class 1 medical they wanted to find out if there was something that could impede myself in say 10 years time and ultimately affect my employment. I was amazed. They must be playing god in trying the predict the future.