Yeah, I've read the gift card thing here before.
I used to try to alternate stores (and living in multiple places helped--long story), but in the last year or so, it was all about convenience and getting that fix asap. That was usually first thing in the morning because I tried to ration myself (eyeroll) and would run out overnight.
So, buying had to take place at 7:xx a.m. It was often at CVS (the same) or Walgreens (I would alternate those). I was buying the cheap stuff, buying at 7 a.m. and, on Mondays if I was tired enough (before work), I wouldn't bother to go to another place if the liquor aisle was still blocked off and I'd have to ask the lady to open the aisle (I lived in a state that didn't sell on Sundays!)
So, with all of those factors, I gave up the game and just faced the facts that we all knew what was going on. Thankfully, they acted like it was completely normal. It sucked, but luckily, it wasn't that busy because other customers don't have to put on a sham about it.