Essentially, the law cuts against the basic notion that practicing in court without an attorney is engaging in the unauthorized practice of law. The reason is that banks and employers are organizations. In practice, they cannot "represent themselves" because they are not people. Paying an employee to represent the institution is essentially like hiring a lawyer without a bar license.
Attorney opinions are mixed on the question of whether this is a good development. On the one hand, responding to a summons of garnishment is fairly routine, and once a bank officer has done it, the procedure varies little in the second and succeeding iterations.
On the other hand, the courts simply are the province of attorneys according to Georgia law. Carving out an exception for garnishment responses makes no sense when there is no exception for other, equally routine legal matters. A strictly libertarian answer to this inconsistency would be to allow anyone, for any reason, to represent a company, lawyer or no. And then we could leave it to lawyers to prove their worth to potential corporate clients.
As this firm practices frequently on behalf of creditors in collections matters, we can say from experience that allowing non-lawyers to practice before courts, at the very least, will increase the rate of error and resultant burden on society in the form of court time and backlogs.