The statue, called Charity, was unveiled in London's Hoxton Square last week outside the White Cube gallery where Hirst's new exhibition is on show. The collection dolls were taken out of use by the then Spastics Society in the mid-1980s after more than 20 years.
Scope would have preferred the sculpture not to be made, but is trying to use it as a platform for debate. Tony Manwaring, chief executive of Scope, said: "The old collection dolls are an undeniable part of Scope's past, but we now focus on promoting positive images of disabled people's lives.
"People should think about how imagery depicting disabled people as vulnerable and pathetic plays in continuing to deny them their full human rights. We hope this will provoke such a debate," he said.
Hirst thinks his art will encourage reflection on the portrayal of disability charities. He said the sculpture "represents the monumental and vulnerable, standing as a massive reproach, as if its size corresponds to the scale of our refusal to acknowledge a failure in charity."
Hirst has made two extra copies of the statue, each valued at £1.5m.
Ben Sear, assistant director of marketing at Scope, said he didn't expect to receive a share of any sale, saying he was grateful for any donation the artist gave. The artist has previously donated two paintings to Scope, raising £130,000.
Sear added that if Hirst had requested support for his project, it would have been withheld. He was still trying to find out whether the charity or the manufacturer owned the copyright, he said.
Maggie Woodward, a Scope campaigner of 12 years, regretted the sculpture's prominence: "Personally, I'd rather it hadn't been so dominant because it brought back feelings from my childhood. I feel that while we accept images from the past, it's difficult to go forward."
Lucia Grounds, the original model for the doll, which was designed in 1964 by her father said: "My father designed it for his company Angal, which still designs collection boxes. I wonder why he hasn't had any acknowledgement."