Why does Sailor V have a crescent moon on her forehead?

She's the reincarnation of Aphrodite, so, like she does as Princess Venus, she should have the Venus symbol, hence the name, "Venus". The crescent moon is the symbol of the Moon Kindom and Crystal Tokyo. That's Usagi's domain, not Minako's. I'm just wondering. I love Minako, bur it kind of irritates me that she has Serenity's symbol while being a less powerful Venusian.