Tell me about a phenomenon in the world that might seem suspicious, paradoxical, or just weird. In particular, it's good if it's a subject that can apply various economic theories.

Here is examples :

Examples of topics include e.g. "The optimum size of the 'firm' in writing (music) industry", "Why do in some sports couches hire players while in others players hire couches?", "Make-or-buy decision in the food delivery industry", "Why do various western universities in China adopt different business strategies?"