James Michael Tyler (aka Gunther) had a serious coffee shop background
He was actually a barista in a real coffee shop (the Bourgeois Pig in Hollywood) when he was hired to be on Friends, and he kept his job for four years while on the show. Tyler says his other office was "very much like Central Perk... I’d have a shift at Bourgeois Pig on a Thursday night, and then on a Friday morning I’d go to the set of Friends and work in a pretend coffee shop. And there was a point when Friends was getting really popular, and I was still working at the Bourgeois Pig... so I’d be there with my white hair serving real coffee and people would come in be like 'can I get a -- what are you doing here?'."
It was also a complete accident that he looked the part
The night before his Friends audition, Tyler's friend, a stylist, wanted to practice bleaching on him -- so he went in with his hair like that the next morning. “I guess the look worked, for like, a barista circa 1994 in New York," Tyler says. He was on the show for a year and a half as an extra before getting his first line.