In Houston, back when 7-11 stores had open fronts (no front wall, just glass doors that slid open leaving almost the entire from of the store open), ice houses were the thing. Basically an open air bar that I assume originally sold large quantities of ice back when home refrigerators were just catching on. Very popular with the working class. Get off your shift at the refinery and stop in for a few cold ones before heading back out in the traffic.
IIRC, at that same time the law in Texas allowed a father to buy his underage teenage son a beer but he couldn’t buy one for his underage wife. True or not, I’ve no idea, but that’s what I was told.
When I first moved to Texas in ‘80, it was legal to have open containers. Thought it was crazy, and it was, but driving across the huge distances in the middle of nowhere for 6-8 hours kinda saw the possible reason. Fortunately it became illegal a few hears later
IIRC, Texas law does allow a parent to provide liquor to their own children (minors), but only for their own consumption. Or, possibly it is a specific statutory exception (i.e. defense) to criminal pros. for furnishing alcohol to a minor. Can’t remember which, as I don’t do criminal def. work. I guess the idea is that if a parent wants to do it for some reason, they should be able to, in their own discretion, e.g. wine at dinner, as a “medicine” when ill, etc. Probably a legal carryover from our Old West days. Texas also has long had a criminal exception that a person cannot be arrested solely for violation of the “open container” law in a vehicle (or solely for speeding!). (how’s that for steering us a bit back on topic? ).
A few years ago, when Texas had adopted the “beer and wine” thing for package sale (i.e. store sales), some restaurant chains here started thinking about the idea, too, i.e. carry out wine and beer. In fact, I was stunned to find out that Sonic Drive Inn was seriously contemplating selling beer, being a drive in. I think the way you would get it to make it legal would be to receive it through their drive thru, not at the drive up parking slots for “curb service”. At the last second, though, they abandoned the idea, probably worried about liability from all their customers driving around impaired after picking up their beer (or again, offending the folk). Phew!
Texas also has long had a criminal exception that a person cannot be arrested solely for violation of the “open container” law in a vehicle (or solely for speeding!). 
(how’s that for steering us a bit back on topic? 
).
I think the way you would get it to make it legal would be to receive it through their drive thru, not at the drive up parking slots for “curb service”. At the last second, though, they abandoned the idea, probably worried about liability from all their customers driving around impaired after picking up their beer (or again, offending the 
folk). Phew! 