There are opportunists that just wait, they are watching all the time.
"We got the beds back with a letter of apology but there is nothing much we can do."
People continued to drop off goods after hours despite signs advising them to contact the shop, she said.
"It's not intended for the general public, it is intended for our shop and all the money we raise goes back to the Papamoa East community, so they are really stealing off themselves."
Last week, one of its volunteers had a verbal altercation with a person who was trying to load goods left outside the shop into their car, she said.
"That is what we are up against."
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Te Puke Methodist Opportunity Shop manager Venna Halliwell said its items were also "constantly" taken and most op shops faced the same issues.
It had a bin at the rear and security lights but they did not make any difference.
People still left items beside the bin or in front of the store where they could be pinched.
"People just go through and take what they want and leave the debris ... they only pinch the good stuff.
"It is very disappointing because actually it's thieving."
The shop also battled a hefty rubbish bill as it became a dumping ground for unsaleable broken items and televisions, she said. All its profits went back into the Te Puke community and the shop would celebrate its 42nd anniversary in July.
Tauranga SPCA Op Shop manager Sharon Leckie said in December a lot of electronic equipment disappeared.
"When I got to work, all the manuals were blowing down the road."
It was gutting, she said, as the money raised went directly to the animals at the shelter.
People tended to go for high-end items such as internet boosters, cameras and new items in boxes, she said.
Another charity op shop, which spoke on condition it was not named, said the shop spent $15,000 a year on rubbish.
"About 90 per cent of the stuff dropped off is rubbish. Our biggest problem is people thinking this is a quick easy way of getting rid of the things they don't want.
"It's shocking. We empty a skip bin every day, six days a week."
Papamoa Police acting Sergeant Tim Bonner said it was difficult to ascertain who owned the property when it was donated to the charity shop and left outside.
It was a grey area and he advised shops to take steps such as using a clothing bin that could be secured.
"Obviously we really appreciate the people that give stuff to charity shops.
"We don't want people to come along and help themselves because that is not the purpose it has been put there for."