Lunch money

Went to an elementary school with Kamiya last week.
Usually we pay our lunch fee every 2 months. But at Kazura elementary we had to pay for our lunch fee every time we visit that school.
Lunch fee is different at each school. at Kazura it's 262yen for every lunch.
Last week I didn't have exact change. I had 261yen in change.
Kamiya said it's ok, she will lend me the missing 1 yen.
But she said, "please give it (1 yen) back to me later"
After she said that, I just gave her my 500 yen so that I don't OWE her that 1 yen.

I mean... how much is 1 yen... 1 cent in Canadian???
Not that I am not going to return it to her...but she still feels the need to make sure she get her 1 yen back.

Sometimes I really think that Japanese people are so stingy when it comes to money matters.