I know Reg. Z says that for the initial disclosure, we must disclose the presence of any charge that may be imposed before maturity due to a late payment (Late Charge) BUT is there any federal requirement to have to send an actual notice informing the customer that a late payment fee has been charged to their account or is that just a courtesy of a bank to do it???
Any thoughts??

Unless it is a state requirement, like NSF notices, I believe it is just an automated and easy way to initiate collection action and to remind customers there is a problem.

In some cases these also deliver your required homeownership counseling notice.