The hotel had strict security procedures, including CCTV and full-time security guards, and the whole hotel was locked down to the public at night, Mr Lumsden said.
"I think it was an opportunist-type thing. Normally we don't have any occurrences like this at all.''
Hotel management handed CCTV footage of the thief over to police, who appealed to anyone with information to contact them
Golf Warehouse Newton store manager Conal Cooke estimated the bag and its contents - which included a set of Mizuno irons worth about $1500 and a set of Taylor-made R11 irons worth some $800 - would cost about $3900 new.
"That's a very good set of clubs, not the best you can get, but still very good,'' he said.
Police asked secondhand traders to keep an eye out for the equipment.
Anyone with information was urged to contact the Auckland tactical crime unit on (09) 302 6656 or anonymously on Crimestoppers, 0800 555 111.
The team and management are no longer in New Zealand.