Humane Society International spokeswoman Wendy Higgins said the auctions raised money for the club's pro-hunting activities. Last year, $2.7 million was raised from the auction of 314 donated hunts.
"Offering pay to slay-hunting trips is grotesque, treating these magnificent animals as little more than living target practice," she said.
SPCA chief executive Ric Odom said the society did not have an issue with hunting for food or as part of pest control.
But it was against trophy hunting, especially by amateur hunters who might not have the skill to kill quickly.
"The whole idea that people are going out and shooting animals for their own entertainment, that's pretty distasteful, and I think a lot of New Zealanders would agree with that."
SAFE New Zealand campaigns officer Shanti Ahluwalia said hurting animals for entertainment was "never OK".
"In hunting, there's a significant chance of mortally wounding an animal so it dies a slow and painful death and it's unacceptable that we are doing this just to entertain a few rich tourists."
But Safari Club International's New Zealand branch president, Mike Knowles, said trophy hunting here had been going on for decades.
The Las Vegas auctions had been going on for decades too, and the proceeds paid for hunting and conservation projects, he said.
Mr Knowles believed trophy hunting was worth $30 million a year to New Zealand's economy, and said guides were bound by a code of ethics.
Deerstalkers' Association national president Bill O'Leary said foreign trophy hunters pumped "tens of millions" into the economy each year.
He said Kiwis also travelled overseas for trophy hunting, and he had no problem with people coming here to do the same, provided they hunted with a member of the Professional Hunting Guides Association.
"I'm comfortable [that] if they're with Safari Club International and the hunt is being offered by a safari park in New Zealand and with [association member] guides, it ticks all the boxes."
New Zealand hunting safari operators who donated packages for the auction wouldn't comment, but one, speaking on the condition he was not named, said clients were "high-value visitors".
"In a week, just for the hunting, they'd pay $15,000. A lot of them will spend another week or more looking around New Zealand and they want to do everything. A lot go and stay at Huka Lodge [near Taupo] or Kauri Cliffs [at Matauri Bay in Northland]. These guys aren't cruising around in a campervan."
On the auction block
•Five-day hunt for New Zealand red deer and tahrs for four hunters and four observers, valued at $92,600. The hunt takes place on private property in the foothills of the Sherwood mountain range, north of Fairlie, and the package includes accommodation, meals, guide and up to four red stags and four tahrs.
•Twenty-day South Pacific all-inclusive full-bag hunt, taxidermy work, rifle and round-trip airfare for one hunter and one observer, valued at $75,150. Guided with all trophy fees covered, accommodation at gateway towns Queenstown and Darwin and offering red stags, tahrs, chamois, fallow deer, Arapawa rams, New Zealand goats, Australian water buffaloes, scrub bulls and wild boas.
•Six-day hunt for New Zealand red stags and Arapawa rams for father-and-son hunters, valued at $17,100. The hunt takes place in the Haupiri River Valley on the West Coast and is guided. Lodge accommodation, meals, trophies, rifle, airport transfers, trophy preparation and shipping to a New Zealand taxidermist is included.
•Five-day New Zealand free-ranging tahr hunt for one hunter and one observer, valued at $7000. Hunt takes place on private property and package includes lodge accommodation, meals, guide, trophy fees and airport transfers.
