Amazon’s AmazonGo convenience stores, which famously lack cashiers and lines, have yet to expand past the company’s home city of Seattle and Chicago. However, the e-commerce giant is planning on opening as many as 3,000 AmazonGo stores around the U.S. by 2021, Bloomberg reported.

The automatic convenience stores would not necessarily be a threat to the many gas station convenience stores around the U.S., like QuikTrip or Casey’s. Instead, it sounds like Amazon’s goal is to disrupt the market belonging to quick-service restaurants like Pret a Manger and Panera Bread that dominate lunch breaks in bustling urban markets.

At AmazonGo, customers scan their phones with an Amazon mobile app at a turnstile as they walk in. They pick out what they want, which generally means prepared snacks like salads and sandwiches at the stores’ current incarnations, and leave without ever going to a cash register. Instead, Amazon technology in the stores detects what they purchased and charges it to their accounts.

The process is not without its flaws; a journalist accidentally shoplifted something from the flagship AmazonGo location in Seattle earlier this year, not long after it had opened. Aside from any security flaws that exist in the system, AmazonGo stores are expensive to set up because of all the technology required to make them work, per Bloomberg.

Amazon is reportedly still working out exactly what the stores will offer by the time they become a nationwide staple. The company has experimented with packaged sandwiches and salads as well as more freshly prepared food and groceries. The idea is apparently to best serve urban workers who want high-quality food without long waits.

There have been previous reports about planned AmazonGo expansion, but none have described plans as large in scope as Bloomberg’s report.

AmazonGo ballooning to 3,000 locations by 2021 would make it a common sight around the U.S. Still, it would not compare, for example, to the nearly 8,000 7-Eleven convenience stores throughout the country.