I'm not familiar with Texas law, I live in Missouri (misery). I ignore the signs; it is only a misdemeanor if in violation...Actually, if your weapon is properly concealed, how is anyone going to know?
Worry not. If you are in a gun free zone and someone attacks you and shoots you, you will have the satisfaction of knowing that they violated the gun free ordinance. Just make sure that when you enter a gun free zone that you carry proper identification so that when the police arrive just after you've been shot that they can notify your family.
Isn't it wonderful how the government takes care of us?