Yes the generator itself can power other than emergency loads but... the other loads will need seperate feeders, transfer switches panels and branch circuits.
The genertor will need a breaker on it for the emergency loads and a second breaker on it for optional loads.
700.9 Wiring, Emergency System.
(B) Wiring. Wiring of two or more emergency circuits supplied from the same source shall be permitted in the same raceway, cable, box, or cabinet. Wiring from an emergency source or emergency source distribution overcurrent protection to emergency loads shall be kept entirely independent of all other wiring and equipment, unless otherwise permitted in (1) through (4):
(1)Wiring from the normal power source located in transfer equipment enclosures
(2)Wiring supplied from two sources in exit or emergency luminaires (lighting fixtures)
(3)Wiring from two sources in a common junction box, attached to exit or emergency luminaires (lighting fixtures)
(4)Wiring within a common junction box attached to unit equipment, containing only the branch circuit supplying the unit equipment and the emergency circuit supplied by the unit equipment.