McNeill says the low-quality clothing that gets donated then adds a cost for the charities that need to sort through it.
"Consider the costs to retailers who have to deal with the stuff they can't sell. They deal with garments that are damaged and can't be repaired, and it builds into their pricing."
She would like to see New Zealand consumers be considerate and conscious when donating items. She says consumers should be encouraged to buy New Zealand-made, sustainable and quality clothing if they are buying brand new and donate clothes to charity if they no longer have any use for them.
"The best product is the one with the longest life cycle".
The Salvation Army's national Family Store manager, Gareth Marshall says there's a perception that prices at op-shops have increased but it's pricing that's set by the market.
He says there is a perception of increased prices, potentially influenced by what he calls a growing 'professionalism' of the Family Stores.
"Demand is high at the moment as people are struggling," Marshall says.