12/27/2011 at 08:00 AM EST
Performing in front of 20,000 people can really work up an appetite.
That was apparently the case for Rihanna
, who popped into a McDonald's in London shortly after her show at the O2 Arena last week.
"It was amazing to see one of the world's biggest female stars queuing like everyone else," a patron told the British The Sun
The singer, 23, reportedly went unnoticed by most of the staff and fellow diners, despite her being flanked at the ordering counter by three "beefy bodyguards."
"She took her food, paid and slipped away," the eyewitness said. "No one batted an eyelid."
– Liz Raftery