He says the move – prompted by his customers – will leave the society hundreds of pounds out of pocket. But he is handing the boxes back – and calling on all other farm-related businesses to do the same.
Mr Haddock's decision to remove the boxes from the Churston Farm Shop, near Brixham, follows a series of outspoken attacks on farmers involved in the postponed trial badger culls by the charity and its chief executive Gavin Grant.
In recent weeks the RSPCA has called on supermarkets to boycott the milk from farms in Somerset and Gloucestershire where pilot culling is due to take place in the spring, and threatened to "name and shame" farmers involved in or supporting the cull operation.
Mr Haddock, a former regional chairman of the National Farmers' Union, said the tone of the statements "demonstrates how the RSPCA has been hijacked by political interests".
He said: "It is supposed to be a charity which concerns itself with the welfare of animals. All farmers are doing is taking part in an entirely legal operation whose terms of reference have been set and approved by the Government.
"There is no shame in trying to rid the countryside of unhealthy badgers which are not only spreading TB among their own population but are doing untold damage to the livestock farming economy." Mr Haddock said he had been a long-term supporter of the RSPCA, like many farmers, and had even agreed to rescued wild animals being released on his land. But he could no longer ignore public opinion.
"It was my customers who really objected to the boxes being there, because they genuinely felt farmers were being stabbed in the back by an organisation which ostensibly stands for animal welfare," he said.
"My customers realise that so long as diseased badgers are allowed to roam freely in the countryside, the welfare of other badgers and of cattle, alpacas, even cats and dogs, will be severely compromised.
"Until the RSPCA comes to its senses and stops aligning itself with the animal rights extremists ... no farm-related business should be supporting it in any way at all."
A spokesman for the RSPCA said: "We rely entirely on public donations and it is a shame if Mr Haddock feels this way, but of course we respect his views. We are very sorry to lose his support and we hope he will change his views."
