You should see the rest of the horrible install!Wow, a professional installer did this? That's poor work. The fact that the speaker is not flush with the bracket is not only aesthetically bad, but also acoustically poor. You will get some midbass loss.
The least he could have done was modify the actual speaker mounting ring, cut a notch like suggested, to accomodate the OEM bolt. Better yet, he should have made custom MDF brackets, then mount to the deck without using that OEM bolt. Yikes.
You should read my entire 3 page letter to the manager. Can't wait to see what he will do to remedy the shitty install and damages.The wood screws are used because of their acoustic properties. They produce a more natural sound by utilizing the course threads, or they were just cheap.