"It's sad that so many came forward, because it meant so many suffered," said Stewart, the former Tottenham, Liverpool and Manchester City striker.
"People will see now how prolific he was and hopefully the people who suffered will not feel as I have, that the police are only interested in the victims of others.
"I'm not bothered that he won't face justice - I never came forward for that - but I'm gutted for those who have reported him and will not see him face justice."
Roper warned Stewart, who started his career at Blackpool, never to tell anyone of the horrific ordeal or risk his family being killed.
Witnesses revealed how Roper abused children on expensive trips to the Far East, New Zealand and America.
Dino Nocivelli of Bolt Burdon Kemp Solicitors, representing several survivors, said: "The number of children who allegedly suffered sexual abuse at the hands of Frank Roper indicates he was a substantial threat to children.
"What is even more worrying is that this is very likely to only be the tip of the iceberg. Frank Roper was associated with Blackpool for over a decade, he was granted frequent access to children as a result of this and the abuse is alleged to have taken place not just in England, but also in Thailand and New Zealand.
"I have been instructed by a number of survivors to pursue claims against Blackpool Football Club. A letter before claim has been sent on behalf of one of my clients to Blackpool, setting out the abuse that my client suffered at the hands of Roper.
"Blackpool have confirmed receipt of these papers, and I am awaiting their response as to whether or not they admit responsibility for the acts of Roper."
A Greater Manchester Police spokesperson said: "We will continue to support any victims of non-recent sexual abuse, and we are working with charities and partner organisations to help provide them with specialist support.
"GMP will continue to inform victims of any updates regarding their complaints.
"We understand that reporting such traumatic events is extremely difficult and we will continue to assist any victims in any way that we can."
Blackpool were approached, but declined to comment.
