I’m not a fan of pranks to begin with but I think it’s cruel to take someone’s food from the communal fridge at work. Food is a basic need. Taking it away from someone goes beyond selfishness. It’s an act of fundamental disrespect and negation of that person’s humanity.
That being said, I also think it’s bullshit when people treat communal eating areas as their own personal pantry. Do you really need to leave 8 yogurts in the fridge, Cheryl? How many dirty coffee cups are you planning to leave on the window ledge, Bob?