The auto harvesters sounds interesting, however in current context the fapets would consume/eat their favorite food (being the main idea about the taming part, that they ignore any threat instinct because of this). Maybe some other resources or just making money. Keep in mind that they supposedly have a low level of intellect, close to animals.
I was thinking about using them in a personal Toilet section of Nishy's bar (after it is leveled up enough), that way they can make money, needing to be h trained to satisfy and survive clients fetishes.