Yep, that's why we need legislation to take carry beyond the powers of the shop keeper and employer to control - except for the techy case.
None of our 'rights' that we think exist in abstract are instantiated without legislation.
Thus, thus the efforts to construct such laws.
They are usually opposed by antigunners and business interests. The latter really don't care about anything but the bottom line buck. They use property rights as a cover for their venial interests.
I understand that carry is not protected. It should be, but in TX - business interests and the almighty buck trashed it. Gun rights spouting legislators and business people forgot about that 'right' for their own perceived financial risk.