A lot of the "gun signs" in Texas are the ones posted in places that sell alky hall but don't meet the 51% rule. I think someone posted that sign earlier. It doesn't effect CHLs, it just makes things worse for someone who was carring sans CHL, which is illegal anyway.
But anyway. Texas is not the bastion of RKBA paradise people think it is. It's true that the laws here are very moderate compared to many other places (no state AWB, no registration requirements, etc.) but other states (such as AZ) are way ahead of us. There's no open carry, our permit is expensive, we have lots of weird weapons laws pertaining to non firearms (Bowie knives are illegal in Texas at least to carry so figure that out), and so on.
The problem stems from the fact that the post reconstruction state constitution was written to cripple the government as much as possible, so once the draconic weapons laws of old were put down, repealing them is just impossible because the state government is so bogged down. Normally a state government that can't get anything done is a good thing, but not when you're trying to pass reforms.
Things move slowly in our favor here thanks to the TSRA, which all Texans need to join. Every year we make a series of small but important gains, trying to gradually shift things in a better direction. Yeah, I'd rather have it all right now, but politically that ain't gonna happen. Texas is a very conservative state in the truest sense of the word: sweeping changes just don't happen, generally speaking.