I’ve seen them packed in 4s as well. 10 packs are common, and I’ve seen cartons of 15 as well. Dunno who determines that. I swear we had cartons of 12 too but I haven’t seen any in a long while. Am I going crazy?
I keep them in the carton in the fridge anyway and my egg shelf has butter and cheese, so problem solved :p
I like to preheat water for my electric stove in my electric kettle. So what if the microwave is also running? Ahh, the power of 230V.