Walmart is the most popular store in America. More than half of all shoppers in the country visit a Walmart location in a given month. No other U.S. store can claim a majority of Americans as customers.

24/7 Wall St. reviewed foot traffic figures at major U.S. stores provided by data service company Placed Insights. According to Placed Insights, which monitors on a monthly basis hundreds of thousands of American consumers, the most popular stores are primarily fast food, discount retail, and pharmacy chains. There is one gas station on the list, Shell.

The nation’s most-visited stores are popular for a range of reasons. One of the main reasons is likely the sheer size of some of these companies. With 14,259 McDonald’s restaurants and 13,626 Dollar Tree locations across the nation, the two stores are virtually ubiquitous. Similarly, Walmart, the world’s largest retailer, has enough stores in every state in the country to be accessible to most Americans.

Click here to see the most popular stores in America.

As the nation’s most popular stores, these companies also tend to dominate their respective markets. By revenue, Walmart is the largest retailer; McDonald’s is the largest fast food chain; CVS is the largest pharmacy; and Shell is one of the world’s largest oil and gas companies. Among the most popular stores, these mega brands also tend to come in pairs. While Walmart tops the list, one of its competitors, Target, is also in the top 15. The Home Depot is the most popular home improvement store at 11th, but Lowe’s is close behind, in 14th place. And while McDonald’s may enjoy visits from nearly half of all American consumers, Wendy’s, Burger King, and Taco Bell are also among the most popular stores in America.

According to David Shim, founder and CEO of Placed Insights, ultimately, the popularity of these stores reflects the desire among American consumers to have choices. Since so many people are visiting so few places, this may seem counter-intuitive. But according to Shim, when it comes to choice, Americans seem to prefer clarity over volume. “People want to be able to choose ‘a’ versus ‘b’ but they don’t want to choose from ‘a’,’b’, ‘c’,’d’,’e’,’f’.”

Price also appears to be a factor in popularity, as more than half of the 15 most trafficked stores are either fast food chains or discount retailers. Shim explained that restaurants dominate the list of popular stores primarily because of the high frequency of visits — but also because the product is very affordable.

Most of these 15 popular stores also wield some of the nation’s largest advertising budgets, which likely helps increase foot traffic. Of the 15 most popular stores in America, 11 are among the 200 largest ad spenders identified by business data tracking company Advertising Age. Walmart and McDonald’s — the first and second most popular stores — spent $866.7 million and $935.1 million on advertisements in 2014, the sixth and fourth largest expenditures respectively.

To determine the nation’s most popular stores, 24/7 Wall St. reviewed data provided by Placed Insights, which calculated the percentage of Americans 13 and older who visited various stores in April 2016. The shares of men and women visiting these stores also came from Placed Insights. We also reviewed U.S. sales and store count data reported in recent company financial documents, as well as advertising expenditure figures from Advertising Age in 2013 and 2014.

These are the most popular stores in America.