Pokemon Go is in Our Nature

My elder sister was relating to my youngest sister how she realised Pokemon Go draws out one's very nature,

"As a spender, I spend my coins from battling in the gym the moment I earn enough.

As a saver, she (meaning me) saves up her coins after battling in the gym."

to which my youngest sister replied,"Hmm ... that's true. I think about how to spend the coins even before I have earned them!"