While there are many millions of coffee drinkers who rely completely on Starbucks to satisfy their coffee urges, more than half of Starbucks’ customers regularly visit Dunkin’ Donuts or McDonald’s for a hot beverage or breakfast over the course of a month.

This is among the findings of QSR^dna, a massive benchmark survey of the annual shopping habits of more than 15,000 quick-serve restaurant customers, conducted by CustomersDNA, a marketing and research consulting firm.

The QSR^dna report found that while 41 percent of Starbucks customers can be considered “loyals” who did not visit any other coffee/breakfast chain during the average month, 53 percent, identified as “roamers,” also stopped by either Dunkin’ Donuts or McDonald’s during an average month.

Shopping patterns for Dunkin’ Donuts’ customers were similar (42 percent loyals and 53 percent roamers). McDonald’s had the most loyal customers, with 62 percent saying they did not visit either Starbucks or Dunkin’ Donuts during the average month.

“The significance of these patterns became clear when we found that the roamers purchased a hot beverage and/or breakfast nearly twice as often as loyals,” says Dave Jenkins, CustomersDNA cofounder. “During the average month, loyal customers of each of the three chains visited their favorite store 6.7 times, while the roamers averaged 13 visits per month. Converting these sometime-customers to loyals is key to winning the coffee/breakfast battle.”

The study examined consumer visit patterns, frequency, and customer loyalty and menu preferences across five purchase occasions (breakfast, lunch/dinner, hot beverage only, cold beverage only, and frozen treat only) over the course of a 12-month period. The report provides chain operators with a diagnostic tool for identifying, evaluating, and attracting high-value customers as well as detailing their spending levels, the items they purchase, and which other chains they patronize.