McKay said police identified the group of doorknockers in Stokes Valley, only to find they were simply a group of Christians "professing the virtues of God" and "turned out to be legitimate".
McKay said what had happened publically with the unruly tourists was making people more cautious.
"As a service we are only too happy to follow up on these suspicious characters, just in case they do have fraudulent ideals, so we encourage people to report it."
The suspected roofing scammers tend to operate through cold calls to households.
The caller would claim they're a contractor who "just happens to be in the area", Detective Senior Sergeant Bridget Doell earlier said.
"But the reality is, they are often just out to obtain easy money and will quickly leave after starting work."
Doell said homeowners often felt pressured to hand over money.
"If you find yourself in this situation – do not engage and do not hand over any money," she said.