Guess the real question is how much if your life worth to you? Not trying to be snide... but I carry a firearm for one purpose... Life insurance. Sure I love target shooting.. but that is not why I carry a .45ACP tucked in my waist band every day.
If I deploy a firearm in a public setting you bet your bottom dollar its going to be to preserve my life, or someone else's life. There are some things worth risking a battle in court for.