I usually don't visit malls that have a 30.06 posting (sign in Texas that owners put up that say you can't wear your gun
) for just this reason. Katy Mills Mall in Katy (just west of Houston) has one. They get very little of my business.
Luby's cafeteria learned their lesson in Killeen, Texas about 15 years ago.
Soon after that event I gather they removed their 30.06 sign. Now I eat there all the time and enjoy their Country Fried Steak with my OP on my hip. I'd rather not be a mall owners educational piece getting shot while unarmed.
I had a very long thread along these lines way back concerning if I had my gun and some islamic terrorists, crazy columbine kidz, or just some nutcase with a brain tumor came in and started "hosing people down." What if your bullet missed or went through the perpetrator and hit someone else...yikes!
on that point, try to make sure you have a clear shot if you can.
If your gun is in your car then the problem is likely to be over before you get back in there, plus you want to be extra careful not to get shot by a nervous mall guard or a policeman mistaking you for one of the bad guys.
Aside from that all I can say is happy hunting and be safe.