You can buy pre-threaded bobbins really cheap in the middle of Lidl/Aldi usually they come in a big pack with a small quantity of thread the same colour.I think I'm going to ditch those bobbins. Even if they would work in my machine I can't imagine a time when I will ever need that many! How on earth did she ever end up with that many??
I bought them before, it's handy if you have children with colourful clothes, that way you usually have a bit f something "close enough" in colour, pop the bobbin in, thread the spool and off you go and you don't end up with your main metal bobbins part loaded with loads of different colours. I have found it helpful to bypass some of my traits and to avoid the "pile" where I think I can't repair thin with white/black thread, I'll get some purple tomorrow, then tomorrow never comes and the child outgrows the shirt anyway but it remains in the pile because "I might use the fabric one day". Trying to make it harder for myself to procrastinate sort of thing.
If you do only big stuff where you buy the matching thread for the fabric and you aren't a procrastinator then it's not for you.