> A microwave?

I do not see why you find this surprising.

There exists no better method for heating the food there, and many kinds of food are much tastier and also healthier warm than cold. They might eat some paste from a tube, but it certainly becomes more appetizing if it is heated.

The cost of having there microwave ovens is low and the improvement in the quality of the food is great. Moreover, they might also be useful for heating water or other things for some of the scientific experiments.