The Mutant Sprouts featured in "Moptop Tweenybop" look a lot different from the ones you buy in the store. But maybe that's because they're ninja sprouts, while the ones in the store are non-ninja sprouts. After all, Mutant Sprouts are said to come in ninja and non-ninja varieties.
In the movie, before Strangeglove sends Shishi through the Glumping machine, she says, "Help me, please!" and he says, "Help? Of course!". While he could be being ironic, it could also be twisted sincerity: he may truly believe that Glumping Moshlings is helping them because he likes Glumps and dislikes (or even hates) Moshlings.
Related: maybe Fishlips finds it liberating dressing up as a Moshling because he was one once. Also, he can be a bit more friendly than most villains. That could be a sign he's starting to de-Glump.
In "Pop Goes the Boo Boo", the Super Moshis mention that Baby Rox will need to rest before her performance, despite her not being sick or anything. This makes sense when you realise she's a baby, and babies sleep a lot.
Speaking of Baby Rox, maybe Strangeglove stole her egg because he knew that the voice of a Glitzy Boo Hoo could power the machine used to smash Rox that he could use for a Super Weapon. However, the Super Moshis intervened and she became a singer, so he had to build the Robo Quacks to take her voice from a distance.