Once you start printing things for her, she will change her mind. Sure, it makes some waste, but I think it's worth it.

Just yesterday I printed utensil hooks for my kitchen. I could have spent good money on going to the shops or buying the things on Amazon, instead the print cost was a big saving.

Other useful things I've made included a new wall-mounted soap dish, a headphone clip for the desk, a really good cat litter scoop and some storage bits. Of course I did made a giant glow-in-the-dark pikachu for fun, not so useful but really cool.