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.
Picture the gladiator riding his horse in the light of the moon yelling, "Do you have any idea how important it is to increase the average pay rate to account for inflation? All of us gladiators are going to be unable to pay the bills soon because inflation isn't being taken into account! You'll suffer too! Listen to me!"
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).
Imagine if you were in this gladiator's place. In five years, you wouldn't be able to afford to eat thanks to the bosses in とうきょう refusing to adjust for inflation. Back in my day, onigiri only cost FIFteen yen!