"To the rest, they are actually depriving their community of funds which would go to help those in need, as getting rid of their rubbish costs our shop a lot."
The shop's co-manager, Dianne Ferguson, said the store also received mattresses and lounge chairs after hours which often were not saleable in the morning.
Strewn rubbish was another issue. "We have a lot of clean up to do in the morning as people have rifled through the bags and strewn them along the footpath," she said.
"[Our volunteers'] time is valuable and it is a shame to have it wasted by the time and effort they put in sorting through all the donations to find those gems that are worth selling."
Several other Auckland charity shops said they had received a large amount of unsellable goods recently.
Emily Dearsly, of Mercy Hospice Shop in Ellerslie, said it was only taking two to three days for the store to fill a rubbish skip, where it would normally take about 10 days.
"Some people seem to see us as an easy way for them to get rid of things."
People often left items after hours directly below a sign which says, "please no donations outside of business hour".
"Some times we have to stop accepting donations for a few hours or an afternoon because we have so much to sort through," Ms Dearsly said.
Salvation Army Mt Wellington shop manager Gary Davison said unsellable goods were increasingly being dropped at his store.
"We recycle as best we can but there's a lot of stuff that gets dropped off -- particularly after hours -- that we can't sell or recycle," he said.
"Couches with rips in them, or that a dog has had a good go at, often get dropped off at night."
Volunteers didn't have hours to spend cleaning couches, or fixing broken items, he said.
"It becomes a health and safety issue if items are too decrepit. We can't give them to families.
"The same goes for any electronic goods which are faulty.
"We also can't sell any clothes which have holes in them or are dirty, or any household items which are broken."
Charity shop tips
• Only donate what you would have in your own home.
• Donate during business hours. Some stores will pick up large items if arranged.
• Clothes need to be clean and not have any holes or rips.
• Housewares need to be in good condition, not chipped, broken or faulty.
• If you'd like to volunteer, talk to a store manager.