Ojamajo Doremi/Fridge

Fridge Logic:

 * If magic spheres are used by witches as currency and witch apprentices to cast spells, isn't that literally wasting money?
 * Yes it is, that why the girls must help at Mahou to earn money and exchange for magic sphere at Witches' World bank or whatever it is.
 * Momoko's ABC song in Motto episode 7 was cute, but how would she even know a song like that if she lived in America most of her life and could barely speak Japanese? Even with the translating headset, that one doesn't make sense.

Fridge Horror:

 * Every Witch gets a Fairy, right? So where are the Fairies of the other Witches? Especially the Fairies of those who're already dead?!
 * Maybe they stay hidden if they're around people their Witches don't know well?
 * In Season 1 Episode 18, Hazuki uses healing magic to heal a bunny she gave to a friend. The bunny's injuries were severe and the only thing stopping Hazuki from suffering the same fate was the Queen of the Witch World using her magic to soften the blow in exchange for Hazuki losing her magic for some time. Since it's been established that healing magic transfers the injuries to the caster and the bunny's injuries were life threatening, where did the rest of the injuries go?
 * Injuries that are life-threatening to a little bunny might be so minor as to be unnoticeable to a human.
 * It was mentioned by Majo Rika In-Universe that Hazuki SHOULD have been near death when she healed the bunny.
 * A bit of Fridge Tear Jerker, but during Episode 46 of Dokkan!, the Curse of Majo-Gaeru was eliminated and all of the Witches who've been turned into Witch Frogs were turned back to normal(except Majo Rika). However, it was established that Majo Monroe died as a Witch Frog. Just how many other Witches suffered that same fate?