Yes, I have an opinion of that dogmatic man, but I'll keep it to myself.
There are many spots indoors that would be comparable to a greenhouse or even to a growing field in a warmer climate. Maybe he lived in a house with the drapes always tightly shut. If they get enough light and are out of the freezing cold, why wouldn't they be happy? There's always the danger of spider mites infesting house plants, but we'll cross that bridge if you come to it.
