Well, there are actually a few reasons...
1. Its my way of saying thank you to all those who mentored me along the way.
2. I get another one of my products in your hands, and when you see how awesome it is, it should get you excited to buy other stuff from me in the future.
3. I'm kinda a show off... I'm not going to lie. I get a deep satisfaction when I hear from Firefighters like you who tell me how the book has helped them.