fast-food drive-thrus could soon use license plate scanning technology to track your purchases and move the line along in San Diego.

The technology works this way: When you pull into the drive-thru lane, a camera scans your license plate, relaying that information to the order-taker. It tells fast-food employees what you usually order and offers suggestions on up-selling. The system can even store payment information, so customers don’t even need to open their wallets.

“Drive-thrus are in the stone age right now,” said Dan McCann, Chief Executive Officer of 5thru, a company now testing and working with fast-food companies to revolutionize the industry.

It’s an idea that has some people concerned about privacy issues, says San Diego State University business ethics professor, Wendy Patrick.

“People are often very private when it comes to their dining habits. They don’t necessarily want all their friends and colleagues to know that they’re getting a Big Mac and a milkshake at the noon hour,” Patrick said.

That’s the least of it. Patrick said some consumers may worry about how their personal information will be used.

“Am I going to start seeing optimized ads for shakes and Big Macs on my computer screen every time I try to do a google search?” Patrick said.

McCann said customers will have to opt-in to use the service, either by signing up through loyalty apps or by telling the cashier at the drive-thru window that they want their information stored.

Some San Diegans said as long as they have the opt-in option they’re not worried about privacy.

“It wouldn’t bother me,” said Ray Co, as he left a Chick-fil-A near Sports Arena.

Zach Gonzales of Chula Vista said the idea of license plate scanners concerns him a bit, but not if he’s given the chance to opt-out.

NBC7 Contacted Jack in the Box, McDonald’s, Starbucks, and Chick-fil-A to see if their restaurants are interested in the technology. Only Chick-fil-A responded, telling us they haven’t tested or implemented the technology.

Its expected at least one major fast-food chain will begin using the technology before the end of 2019. McCann declined to say which one.