I just thought about this today. Every time you are transacting with bitcoin, you will be told that you have to wait for bitcoin confirmation. This is common with bitcoin gambling sites. What I know is that bitcoin transactions are irreversible. Then why is it that you have to wait for the confirmation before initiating anything?
It is done for security reasons and so that you can be protected by yourself and the other user also gets protects himself. If this would not be people would double spend it and it would create caous. It's irritating but it's for our good only. So try and bear with it.