Stats NZ figures show household expenditure on food increased by 28.1 percent between June 2019 and 2023. Photo: 123RF
From product placement to the rising cost of basic food items - there is a raft of reasons why a trip to the supermarket can be a challenge for your mind and your wallet.
The weekly shop has become one of the main expenses for many households.
Between 2019 and last year, the amount households spent on groceries shot up 28.1 percent, according to data from Stats NZ.
"If things are going to waste in your fridge ... then that is a way of overspending" - Ekant Veer
Marketing professor Ekant Veer, told RNZ's new podcast Thrift, that supermarkets had always wanted to target shoppers.
"It's just that the tools have become more savvy and therefore it feels more effective as they're targeting us.
"There's more data out there about us, there's more things they know about consumers and they use that to try and get more money out of our wallets."
But it was not always the supermarkets that were responsible for us overspending, he said.
- Listen to Supermarket Strategies, episode one of the podcast Thrift.
Veer said the problem could stem from wasting food at home.
"If things are going to waste in your fridge, the perishables are going off, then that is a way of overspending."
People should only buy what they know they will be able to use that week before it goes off, he said.
"However, we kind of go into supermarkets a little bit mindlessly, and as a result we pick up stuff that looks good or we feel we might want and not actually need."
Tips for avoiding buying things we do not need included having a supermarket shopping list and sticking to it, he said.
"If you want to reward yourself do it, but do it on a small small scale like a chocolate bar or something like that.
"Don't go in and then suddenly grab four bottles of wine when you're only after one bottle of milk."
People should also not go to the supermarket when they were hungry because it made it more likely they would buy something to sate their hunger, he said.
It also paid to look around the shelves rather than just looking at eye level because similar cheaper products might be hiding up high or lower down on the shelf, he said.
It was not just children who lacked will power when shopping - it could be a partner, he said.
"I know I'm like that sometimes and sometimes it's easier for my wife to go shopping without me cause I'll grab a bit of cheese or whatever else it might be.
"But that pester power from someone who wants things but doesn't necessarily need it is going to impact on your wallet."
If possible it would be best to not go shopping with those types of children or adults, or doing your shopping online at home and then picking it up later was another way to deal with it, he said.
Marketing in New Zealand must conform to the Advertising Standards Authority, but Veer said that did not restrict some strategies to sell products.
"There's nothing stopping a supermarket from putting a yellow sticker say that says this is on sale and the sale is only two cents. But that yellow sticker is enough to go 'Oh that's on sale, I'm saving some money, I'll grab that'."