Alcohol laws in Texas have been historically restrictive and confusing. In Dallas County, alcohol sales varied precinct-by-precinct. To have a beer in a restaurant in a 'dry' precinct, the restaurant would have to be considered a 'private club', and anyone drinking would have to be a member.
Enter the "UniCard", where you pay a restaurant $1 for a membership card, and you are instantly a member of all subscribing restaurants/clubs in the area. Silver City Caberet near downtown Dallas apparently did not join that system, so you would have to show your license to be scanned. The same was true at Illusions, which became The Penthouse Club, which became XTC.
For any given precinct to change their status from dry to wet, they would have to have a vote. Starting from where the precinct lines were the last time the precinct was voted 'dry', they would have to approve the change. Then, they'd have to vote again within the current precinct lines. Only then could they get rid of the UniCard requirement for bars/restaurants in that precinct.
When the Cowboys played at Texas Stadium, the city of Irving was dry. Beer sales were not allowed in the stadium. Eventually, the team won approval for a 'corral', a roped-off area in the parking lot where they could sell beer. At their new stadium, $14 gets you a margarita in a plastic cup.
Years ago, I lived in an apartment complex in Grand Prairie, staddling the line between Dallas and Tarrant counties. The Stop-n-Go at the western end, in Tarrant County, could sell beer. The one at the other end couldn't.
It's ridiculous laws like this, passed over a hundred years ago, that require a club to scan your ID. Because only members can drink, you see.