In this case I don't really see a distinction. Sure, if an employer wanted to pay overtime to an exempt employee they could, but an exempt employee has no legal expectation of receiving overtime. To me, that's not being eligible for it. If the employer chooses to expand eligibility he can, but the law is not under any circumstances going to require it.

But that's all semantics. We're in the same place, I assume. The fact that the employer uses a payroll system that defaults a standard number of hours does not affect the employee's status or what he is entitled to.