What makes dresden files so good is that dresden knows this, and he abuses the hell out of that. Time and time again he gets the jump of his enemies because he thinks outside of the box like that haha.
And same for marcone, he knows that with the right bullets and tools, common items can hurt the supernatural. Its also what imo makes the supernatural in the series so real, they are extremely powerful, should be feared but all of them have a weakness. You just need to know it. And like dresden said so much, knowledge is power!