Enter the world of imagination:
Alright, so the evolution thing hasn't been done in the manga, that dosen't mean it can't be done. Also, we haven't seen a lot of Amanda, maybe she is kind of arrogant, or maybe she does like cleaning things, and Cheren's Snivy has been shown to like battles, almost like Amanda.
In the games, Hugh's late grandfather got the Purrloin for his sister and stolen by the Shadow Triad, I wonder why Kosuka didn't go with that background story instead of making a brand new one. Imo, it would have been more epic if some 3 punks came and totally demolished 2 little kids and took their Pokemon.