The commission said the merger would see Foodstuffs become a single national grocery entity - further reducing competition in the market.
Now there are calls to better regulate the "wild west" industry after safeguards were removed in 2017.
Woolworths says members could be earning rewards over twice as fast as the previous programme.
It's looking into the major supermarkets' pricing and promotional practices.
"The evidence would suggest Temu are scraping data, and probably aren't just a retailer."
Here's what you should consider passing by during your next Kmart haul.
Could 'fake-aways' be the answer to Kiwis' money woes?
It comes amid a $400 million overhaul that has seen Countdown rebranded as its parent company.
The polypropylene sipping cups are marketed as safe for children over six months of age.
