Charlie Angus, the NDP critic for ethics, said the revelations show the Conservatives have become apathetic about enforcing spending rules at federal organizations.
"They are obsessed with managing spin, but not managing the department that they're overseeing," Angus said.
"This kind of behaviour can only happen in a culture where there's a sense that the top boss isn't really all that interested in whether or not the rules are being followed."
CBC's the fifth estate reported Tuesday that over at least the last five years, the mint has paid for staff and senior executives attending international coinage conventions to go on sightseeing and networking junkets in the days after the conferences officially end.
Following a congress last year in Mexico City, for example, 11 mint staff and executives — including a Conservative appointee to the mint's board of directors — headed to a luxury beach resort near Cancun for three days with dozens of other conference delegates. The official itinerary for the "post-conference tour" included a beach party, gala dinners and a trip to some Mayan ruins.
In previous years, personnel went on post-conference trips to Australia's Great Barrier Reef, a Thai beach resort and the Austrian countryside.
Mint policy also allowed senior executives to bring their spouses on the trips, at a cost of tens of thousands of dollars over the years.
"Why the heck is spouse travel being expensed?" Angus said. "There has to be a standard for protecting the Canadian taxpayer."
Liberal critic Geoff Regan weighed in as well.
"I think this is the kind of thing that sends people's cynicism sky high," he said on CBC's Power & Politics.
"To have a Conservative appointee taking these luxury holidays.… I think people are outraged at that."
Even Finance Minister Joe Oliver, who initially declined to comment when the fifth estate first contacted his office last month about the mint's expenses, had stern words on Wednesday.
"Abuse of taxpayers' dollars is unacceptable and will not be tolerated," he said in the House of Commons in response to an NDP question period broadside.
"While the mint manages its own expenses, like other Crown corporations, it has a responsibility to ensure public funds are managed frugally and in the best interests of taxpayers."
Mint repeals policies
The mint, under new management since February, has since repealed the policies that authorized expensing the after-conference tours and spousal travel.
It said it implemented the changes to meet the "expectations Canadians have of a Crown corporation" and to conform to "best business practices."
That's a turnaround from last year, when mint spokeswoman Christine Aquino defended the practices.
At the time, Aquino said the post-conference trips provide a valuable chance to connect with "key suppliers and customers."
As for paid spousal travel, she said then that it is "a business expectation … for officials within the minting industry to be accompanied by their spouse for important occasions."
A spokesperson for Oliver said paying for spousal travel was wrong and should have never been part of the mint's policies in the first place.
Wednesday's ruckus over the mint's spending hearkened back to a decade ago, when the tables were turned and the opposition Conservatives were taking the Liberal government to task for the expenditures of previous mint president David Dingwall, a former Liberal cabinet minister.
Dingwall's spending was "scandalous," Stephen Harper, the Opposition leader of the day, railed. "Will the prime minister now do the right thing and ask the auditor general to do a thorough investigation?"
Dingwall made headlines the next month when he testified before a Commons committee.
Explaining why he might deserve severance pay even though he had resigned amid the brouhaha over his expenses, Dingwall famously said, "I'm entitled to my entitlements."
External auditors ultimately cleared him of any wrongdoing.