More than dorm rooms where such things were usually banned, these were popular with vacationers renting cabins. Westinghouse used to advertise their roaster oven, the original black one, for this purpose also, which is a reason why the broiler/griddle was offered as an accessory. This type of product became popular with the increasing affordability of the automobile when Americans of more modest means were able to hit the highways. The fact that the mother was stuck with a primitive cooking arrangement while the family played on the lake all day was lost on everyone but the mother. Sometimes this was included with an icebox, not refrigerator, in a bungalow so that it could be said to have cooking facilities. In the Catskills, this was known as a kochalayn from the German "koch" meaning "to cook" and "allein" meaning "alone" for families that could not afford to stay at the fancy shmancy hotel and pay for meals at the resorts, but could still be on the grounds for the other joys of the vacation.
I have a Universal brand "portable" oven from the same period without the surface units that weighs a ton because of the insulation.
