By Maria Medina

SAN FRANCISCO (KPIX 5) — They’ve got everything you need to prepare the food, but “ghost kitchens” don’t cater to actual customers. They’re helping some eateries expand and helping others get their feet wet in the restaurant world with less overhead.

The restaurant chain “B Good” offers a healthy menu including chicken, salads and wraps. But there’s something missing at its Chicago location. There are no seats or customers.

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All the dishes made there are for delivery only; it’s what’s known as a ghost kitchen.

“As real estate prices go up and rents go up in prime locations here in downtown Chicago, there’s restaurants that are looking to have their footprint here in the city that just can’t afford to do your traditional brick and mortar,” said William Burns, general manager of the B Good Chicago ghost kitchen.

These types of kitchens have become popular with the explosion of traffic on food delivery apps like Grub Hub and Uber Eats, and that’s why established restaurants are also getting in on the act.

Frato’s in Illinois is known for its pizza, but the company is also making sandwiches in the kitchen and delivering them under the name Cheesy Deliciousness.

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“You have to try to see what trends are coming and try to get ahead of the game on that as much as possible,” explained Michael Kudrna, owner of Frato’s.

It’s a similar story at another restaurant in San Francisco. Customers come to Top Round for the roast beef, but owner Ricky Lopez saw a market for more. He now uses the kitchen for three delivery-only restaurants with specialties ranging from chicken to ice cream.

“You can use your existing team and just brings in more, you know, opportunities that make more sales overall,” Lopez said.

It’s a business model that’s just taking off. Market analysts predict significant growth in digital restaurant orders this year.

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San Francisco-based DoorDash is the first food delivery platform in the country to venture into the ghost kitchen market. It rents out space in Redwood City to brands like Chick-fil-A, Halal Guys and Humphry Slocombe.