The garment barely covered the 42-year-old's cleavage during her first public appearance at Air New Zealand Fashion Week.
Designer Richie Rich said he thought the scarf "works better this way".
Rich, his partner Joe Green and Anderson also met actress Lucy Lawless on the set of Spartacus: Blood and Sand.
Today, Anderson will take to the runway to launch Rich's range "A*Muse" of swim, casual and evening wear.
New Zealand is first stop on the range's tour because of its clean, green image, and Anderson is the "muse", according to Rich.
Arriving at the media centre yesterday, after torrential rain held up proceedings, Anderson giggled and twirled for the cameras.
"I just wanted us to be late so we could drink more champagne, which we did," she said.
Spotting James Somerset, from Prime TV sports show The Crowd Goes Wild, Rich said, "Oh, he's cute," before Anderson demanded he strip off his top.
When questioned about her outfit, Anderson said: "I'm covered . . . what do you mean? I'm not self-conscious."
She said she would rather be naked than wear a bikini.
Anderson knew about the All Blacks: "I heard your rugby team was hot, you promised me hot rugby players."
Former rugby player turned television presenter Karl Te Nana later gave her a cultural lesson with an onstage hongi.
