I have two valid Texas Drivers Licenses at the moment.
I see what is happening here! The Federal DHS and REAL ID requirements are both already in place in my state (Indiana).
But your state (Texas) and the OP's state (N. Carolina) are among the states that are NOT compliant with this Federal law yet, and are on extension. Florida complies with DNS, but not REAL-ID (hence letting you keep the second ID with a notch).
One is not allowed to posses more than one REAL ID (this is the ID that the DHS, TSA, ATF, etc. will require prior to boarding planes, entering Federal buildings, buying guns, etc., and currently some states like Illinois, Texas, and NC are not compliant with, but they are allowing people to use the old/existing ID's as states move towards compliance, because there would be riots in airport lines if they didn't!).
In short, once Texas gets straight with Uncle Sam on Federal ID requirements, your second ID card will either be revoked (my second ID was revoked many years ago by Indiana as part of this process) or rendered useless (won't be able to use it to get on planes, etc., as only the "Gold Star" REAL-ID's will be accepted by the Feds).
That is also why the folks at WalMart in NC didn't care about the second ID. In Indiana, it is against the law to have a second ID (since we are in compliance with REAL-ID and DHS laws).
In NC it is not against the law to have a second license, as it is not yet compliant with DHS and REAL-ID. But it will happen (original deadline has passed, but extensions to get on an airplane for states in process may be granted until just Jan 2018).
So look at your state-issued ID. If you have a gold star ("stars upon thars", to quote Dr. Seuss's sneetches), you are REAL-ID compliant. If not, your state will be either filing lawsuits, asking for extensions, or taking your second ID's and issuing (just ONE!) DHS compliant ID!
From the Code of Federal Regulations:
§37.29 Prohibition against holding more than one REAL ID card or more than one driver's license.
(a) An individual may hold only one REAL ID card. An individual cannot hold a REAL ID driver's license and a REAL ID identification card simultaneously. Nothing shall preclude an individual from holding a REAL ID card and a non-REAL ID card unless prohibited by his or her State.