I called them "insulated aluminum containers" because the spell checker on my phone was having a fit about the nomenclature.

We went through "thermites", "termites"...
I commonly shake my head at some in here who pretend to have military experience, as it is so completely obvious that they have absolutely no idea what in the hell they are talking about. They have likely never really served, so simply can not comprehend what the military is capable of and how they do it.
Now in my over two and a half decades of service in two branches of service, I have had a wide background in how these kinds of things work. And for those who have never served, this will give them an idea how things really work in the real military.
Now my first unit was a Marine security force. We had 24 hour duty days, timed to start and end during morning chow. The ongoing shift would eat hot chow in the morning at the chow hall before taking over, the off-going shift would eat morning chow at the chow hall after getting off duty. For lunch and dinner, they would truck out our meals in mermites to our guard shack. Lunch was hamburgers or hot dogs, dinner was whatever the main meal for the day was.
After a couple years of that I moved to the "Real Infantry". And there, we spent 1 to 2 weeks in the field at a time or more. And we simply expected to eat every meal during that time as MREs. In a 1 week field exercise, we might get hot chow brought out to us once, maybe twice. But we had no field kitchen, it was trucked out from mainside. And having no mess tent, we just ate as we always would, in the open air.
Ever had a dinner of spaghetti outside in a North Caroline summer? During a rainstorm? I have, still a happy memory to this day, as we had been in the field for a week and a half. Finally getting a hot meal, and having to scarf it down as fast as we could or the rain would wash away all of the sauce. It sucked, but we were happy because it was hot chow.
And during my 10 years as Marine Infantry? Never once did I ever see a cot, or sleep in anything other than under the open sky, or in a 2 man shelter half (think of a floorless pup tent where each person has half of the tent).
Then I moved to the Army and was in Air Defense. Very different indeed. No more shelter halves, we had large tents that could be fitted together to hold anywhere from a Squad to a Company. And no more sleeping on the ground, everybody had a cot. That was like the Taj Mahal for a poor grunt like me. And even in the field, 2 hot meals a day was the norm. Breakfast and Dinner (including omelets to order), the only MRE was for the noon meal. That was little different from being in garrison. And served out of an MKT. With an actual "dining tent" where we sat at field tables in field chairs and ate under cover.
But then in my final decade, I was in Army Medical and assigned to a CASH (a modern version of the old MASH). Oh boy, yet another level of comfort I had never imagined. Now there we could eat three hot meals a day. And not only that, something I had never before experienced in all my years in the Army or Marines. Clean uniforms Hot showers!
Yep, one of the things about a CASH unit is that one of the sections is "Laundry and Bath". And just as the name suggests, that is a squad sized section that provides the hospital and all those working in it clean uniforms and hot showers. Which should be expected, we are a field medical unit and can not be expected to wear the same filthy uniforms for 1-2 weeks when treating patients. So in the evening we would trudge over to their area and have a hot shower, and turn in out uniform. And sometime in the next day one of them would return it nice and clean.