I don't know if it's a regulatory issue or more a matter of practicality / best practice. We code them separately on the system so we can pull custom reports for internal use or for regulatory review; and so any overdraft or past due notices go to HR before delivery. This is one of those "we've always done it this way" deals & I've never had occasion to research the reason why.
Opinions are Bartman's, not those of my employer. "A noble spirit embiggens the smallest man."