Basically there is no difference between offline or online business in terms of working hours.Person who manages or own a business generally works more hours than those who are employed.But it is at initial stage of business set up.Once you are established you need not have to work always that way.Even in brick and mortar business,the same theories applies.Once your mortar and brick business is perfectly established ,you need not have to work more than the employees as you can hire a perfect person to oversee the your supervision.