Back in the 80s, I had the Bob and Doug McKenzie album The Great White North. One of the classic tracks from that album was their Christmas song, The 12 Days of Christmas. On day six, their true love gets them 6 packs of two four (and I only know that because I just now looked up the lyrics).
It occurs to me that this idea of a lower alcohol beer sold to junior enlisted may have been an urban myth - kind of like the idea that Mess Hall food was spiked with saltpeter in order to curb the horniness of young men.
It may still be where the “2-4” reference comes from, though.
3.2% beer was a real thing in the USA. Still is in some of the more benighted regions:
I suspect the association with the military is more a matter of lots of military posts being in the Bible Belt states that kept the 3.2 laws on their books long after Prohibition ended. And lots of folks from less uptight states entered the service and got stationed in said Bible Belt. SO they associate the 3.2 beer with the service itself, when it’s really which state they served in.
Some of you are thinking about this too hard. The gift is just six 2-4s, i.e. 144 beers. “Six 2-4s” doesn’t fit with the meter of the song, so they make it “six packs of 2-4” which is something no one would ever actually say. No one would ever actually say “lords a-leaping” outside of the context of this song either.
Yes, it’s dumb. Have you seen Bob and Doug sketches?
I turned 19 while stationed at Great Lakes Naval Training Center in Illinois back in 1975. While I was 18, I could only drink 3.2 beer at the EM club. The day I turned 19 I went to the EM club looking forward to having my hand stamped with a 19 instead of the 3.2 stamp. That meant I could drink full strength beer and wine but not liquor. Much to my regret the next morning, the guy doing the stamping gave me a 21 stamp on the back of my hand. I spent the evening enjoying $1.50 cocktails and eating pickled hard boiled eggs. I had to stand a 4 hour watch from 8am to noon the next morning with a ripping hangover. I learned a valuable lesson that day, hangovers really suck. In the 45+ years since, I can count on one hand the number to times I woke up with a hangover and the last time was at least 30 years ago.