$10 is maybe a bit much, but I think the principal is fine.
Last year, I received emails from a bank I used 10 years ago, asking me to contact them. It turned out they'd been writing to an old address. I thought I'd closed the account, but it had £0.75 in it.
The bank spent much more than that trying to contact me, and I wasted far more time than it was worth closing the account. (They were used to the problem, I asked them to donate the money to charity.)
I assume the situation is this:
They have loads of dormant accounts that haven't been used in years but that have a few dollars on them. If they want to close these accounts, they have to find those people and give them their $7.59. By having a $10 fee, they can empty those accounts within a few years and then just close them without investigating anything. This would take significantly longer with a smaller amount.
Last year, I received emails from a bank I used 10 years ago, asking me to contact them. It turned out they'd been writing to an old address. I thought I'd closed the account, but it had £0.75 in it.
The bank spent much more than that trying to contact me, and I wasted far more time than it was worth closing the account. (They were used to the problem, I asked them to donate the money to charity.)