Strongest alcoholic drinks I can get on a Sunday in the US?

So, liquor stores are closed on Sundays, fair enough. Quick shops like Jiffy Trips are at least open though. I typically go for thunderforce beers and bottles of wine when these are the only options available, but are there any stronger options that I haven’t considered? Trying to save money and avoid high calorie options (because I’m obviously trying to be healthy). I guess my question boils down to: what is the strongest/highest alchohol percentage drink you can buy at a U.S. quickshop?