In three countries, I've lived with four Germans and one half-German. They've all been interested in what I eat.
I think it's irritating, but I also think that the Continental tradition of "enjoy your meal" is annoying in general. Paying attention to somebody who is eating seems rude to me, an American. Not so to the European. And the Germans they want to talk about it.
The Germans appear slightly annoyed, for example, when I eat potatoes in the morning.
It's conspicuous to most Europeans, and apparently strange even to the Irish.
But the Germans take it personally.
Sometimes I feel like the German housemate is worried that one of their guests might see me cooking something that they'd have to explain.