Inflation
While the moon is out, a gladiator is riding a horse, yelling about inflation. No one would listen to him during the day, so he waited for the moon to rise so he could complain about prices doing the same.
とう
あが, のぼ
None
Inflation rises the most in とうきょう, and the gladiator knows that because that's where most of them live and fight (and die).