Eating Bots
With artificial intelligence becoming more capable over time the goalpost of being human, alive or even (generally) intelligent has shifted. One major aspect of life that somehow seemed essential to living yet a waste for machines is being hungry or the act of eating. Both preparing and consuming food actually contains a fair amount of labour. As living beings we don't have a choice but to eat, our lives depend on it after all. There is something about the act of eating that wants to make us believe that the actions are tied to a process that involves thought, decisions and intention.
The 2800 pound car eating Robosaurus is a fire breathing robot that eats cars for our entertainment. Commentators identify actions like, removing the shell, lightly barbecuing cars or even fully cooking them after taking a bite. Even though the robot was not build with explicit emotional expressions, its slow operation (or perhaps even slight malfunctioning) is quickly joked about as being a picky eater. Even followed up with a justification of why it doesn't like Toyota's.
Bots that have utility beyond entertainment, like the Robie coin bank, use eating as a mechanism to encourage the people that interact with to it repeat the behaviour. When Robie gets a coin it swallows it and moves from left to right while chewing on it. After a while he looks up and moves his tongue. An observer can easily interpret these actions as enthusiasm and expressions of enjoyment in response to the delicious meal. Because this is a set sequence of actions in a short timespan its actions seem less decisional. Us humans can still relate to to this behaviour because in a way there is food that involuntarily makes us happy because we like it so much.
The examples above use eating as a mechanism to make the bots seem more alive. If I were to construct an eating bot myself I would add an additional action in the process of eating: the expression of disgust. I envision a bot that is in practise a modded vacuum cleaner, transparent enough to see what happens to the materials inside. People are able to leave 'food' in a bowl for the bot to eat. The bot will suck the food inside with different intensities and durations to emulate the willingness to eat the material and intension behind trying (or being hesitant to) eat the material. If the bot likes food it will generate delightful sounds. In reverse if it dislikes the food it will generate unsatisfying sounds and might even spit out the food.