Wells Fargo, in our case. They started adding $20-30 fees, just arbitrary. A couple of months in a row, despite assurances from branch, crediting the charges back, etc.
We told the manager if it happened again we would close our accounts with them. It did, so we closed the accounts and severed the relationship.
If we started charging our clients ‘arbitrary’ fees, (1) they wouldn’t pay them, and (2) they’d cut us loose on the spot. Pretty unbelievable.