Sure. But in terms of compliance costs, an active account costs just as much, and perhaps more (if there are compliance costs per transaction, not just per account).

> Not to mention that the bank makes a spread on deposits

They make a spread on money left in the account. But I can leave money in an inactive account, too, and they make just as much money on that.

Edit:

I did a little research. Bank of America has no dormant account fee that I can find. SunTrust does[1]... but only for Florida accounts, for some unknown reason. This may be a jurisdictional thing.

[1] https://www.suntrust.com/content/dam/suntrust/us/en/personal... (page 6)

"From 6 April 2016, 'active member discounts' are banned. This means you are not allowed to charge the pots of non-contributing members more than you would have if they were active members contributing to the scheme. Employers are still permitted to pay charges on behalf of active members so long as the total charge level imposed is the same for contributing and non-contributing members. ...The ban applies to non-contributing members where at least one contribution for them has been made to your scheme on or after 6 April 2016. The contribution needs to have been made while they worked for the employer who is using the scheme to comply with their automatic enrolment duties." https://www.tpr.gov.uk/en/trustees/managing-dc-benefits/5-va...

Something similar: fees for dormant prepaid card accounts.

My guess is that even though your funds provide some sort of float to the card issuer, it's still a liability on their books that they need to somehow manage.