My DD is like your DD. She is not into video games or makeup/skincare, which is what kids this age like spending money on. She loves books, but there's the library for that. We buy her food and clothes. She just doesn't have anything she wants to spend money on.

She has a bank account with $1800 in it just from birthdays, a small allowance, and other gifts from grandparents and her aunt. I told her this summer, we would kick in an extra $1200 and she can buy a vanguard fund. She's excited about that.

Maybe it's men's thinking versus women's?
I know about 10 people who spend constantly. They don't have much to show for 30 years of work. They are low on dopamine.
The packages come, they open them, and throw the product somewhere in the corner. The homes are also full of crap.
All are fairly intelligent, but very narrow knowledge. Some have ASD and/or ADHD.

One marker of intelligence is the ability to delay gratification

We have 12 years old twins. We have been giving them money here and there over the past year. They also get money from grandparents etc.

1 year later our son has $20 left and his sister $600. In school, our son has an 80% average and his sister 99.7%

Maybe smart people are just better savers and from a young age.