With the new law they will have the option of a 30.07 which prohibits open carry on the premises.
So they can post a 30.07 but not a 30.06 and you can carry concealed but not openly. In this way they can play the fence between responding to customer who think guns are scary, and acknowledging the right to carry - concealed.
Regarding the comparison of Right To Bear and "Make my damn cake" - yup.
If the store posts a 30.06 sign can I still carry my Mauser?
Businesses must post a no open carry sign in accordance with the requirements of 30.07. Just a “No Open Carry Allowed” or pistol with a circle and cross line isn’t sufficient to get you a misdemeanor charge if you don’t leave when asked.
Then again, always good idea to follow up with a phone call to the business telling them you were turned away and won’t be visiting their establishment again.
From the Texas Dept of Public Safety website:
“Effective January 1, 2016, it is a Class C misdemeanor punishable by a fine not to exceed $200 for a license holder to carry a concealed handgun onto private property after receiving effective notice under §30.06, Texas Penal Code, or to openly carry a handgun onto private property after receiving effective notice under §30.07, Texas Penal Code. Note, after January 1, 2016, the offense will be enhanced to a Class A misdemeanor if it is shown at trial that, after entering the property, the license holder was personally given the notice by oral communication described by Subsection (b) (of §30.06 or §30.07)and subsequently failed to depart. “