Do you need a rooster to raise chickens?
The rooster will also help them find food but sometimes this is more a ploy than an actual benefit to the hens. As the rooster will use a food call to get close enough to the hens in order to mate with them. This said the rooster remembers places where there is plentiful food and will lead a flock time and again to such a place in order to take advantage of it.
If you raise your hens without a rooster invariably one of the hens will assume the role of rooster. This is nature's way of filling a gap and is part of the pecking order but I find that a real rooster does a better job than a hen pretending to be one. A hen pretending to be a rooster will also be more concerned with deciding who is boss and who gets the most food than protecting the flock. A rooster that finds food will make sure that all the hens know there is food nearby, whereas a hen pretending to be a rooster will simply try to keep the food to herself.