"[With] Pak'nSave (and every other Foodstuffs retail and wholesale brand) going single-use plastic bag free, it also means online shopping is that much more convenient for customers who still struggle to remember their reusable bags."
Pak'nSave is the last of all three major supermarkets to introduce e-commerce to its business mix.
Rival supermarket brand Countdown has offered online shopping for more than a decade.
Foodstuffs' New World also offers online shopping and click and collect, which Quin said was experiencing week-on-week growth.
Figures from BNZ show annual online spending is running in excess of $4.5 billion in New Zealand, with the groceries category experiencing strong growth.
Retail analyst Chris Wilkinson said it was expensive to implement online shopping, which was likely the reason it has taken Pak'nSave so long to introduce the feature.
"Online shopping in New Zealand, because of its scale, is both complex and expensive. Overseas supermarkets use what they call 'dark stores' - this is where products are picked [according to online orders] and in many cases packed automatically," Wilkinson said.
"In New Zealand, we haven't seen that happen yet so there's a real challenge in terms of getting the cost model right, and it's likely that model is not right yet."
"Dark stores" are highly automated supermarkets - without customers - dedicated to service online grocery shopping in markets like the UK and US.
Wilkinson said with time and customer demand for online shopping, supermarkets here would have to introduce similar distribution centres.
"Online shopping is becoming increasingly popular, and it goes wider than just customer shopping. Countdowns are supplying a lot of businesses, such as childcare centres, so it's taken on quite an interesting dimension."
Countdown began trialling online shopping close to 20 years ago.
