Neptune's Net is the only restaurant on the PCH in that area, but I don't think that's the reason for it's popularity. It's a casual place across the street from the ocean with plenty of parking. It draws bikers to tourists to celebrities. There's generally a line. You order your food (fried fish, burgers, salads), pay, and then wait at one of the picnic tables until they call your number. The food is good to very good. The fish is fresh, they have a good grilled chicken sandwich. There is beer and wine available. There is a separate line for steamed seafood and another for frozen custard, so don't wait on the long regular food line if that's what you are looking for. They are open 7 days a week. The pricing is fair. After eating, be sure to walk off some of those calories by taking a walk on the beach across the street.
One major gripe: The restaurant does not have a bathroom, they use several outhouses - all of which were filthy when we were there.