Not for you, but it's an issue if you're using Mac Minis as unattended service devices that are hard mounted and will occasionally need to be reset by hand (think kiosks and AV systems in conference room).
Wouldn't you just pull the power cord at that point? If the device has become completely unmanageable such that it needs a power reset i'd be surprised if there's much more harm that way than holding down the power button until it turns off.