Actor and cancer campaigner Samuel Johnson has taken aim at charity muggers – known as “chuggers” – who ask for donations on the street, calling them “snakes” and “dogs”.

Speaking to Channel Nine’s Today show, Johnson said he had no time for the aggressive tactics of street fundraisers.

“Chuggers are slugs, they’re dogs,” Johnson said.

“I’ve really got no time for them to be honest. They’re snakes. Sharks.”

Johnson was on the program promoting Play for Purpose – a new charity formed with the aim of disrupting commission-based charity fundraising.

Virtually all face-to-face fundraising conducted by agencies is commission-based.

But a report released last year by the ACCC found that, assuming an average of 12 times the monthly donation as a fee to the fundraising agency — and the donor giving for around five years — approximately one year’s worth of donations actually went to the agency rather than the charity.

Fundraising agency Appco Australia stated in a press release last year that over the average three to five-year period, “the one-off fee paid to Appco Australia equates to approximately 9 per cent to 30 per cent of the total donation”.

Johnson said although such agencies were not doing anything illegal, donors should be wary.

“If you’re not prudent about how you give, if you don’t know about the organisation you’re giving to, then I’d be pretty cynical about how much is ending up at the cause,” he said.

His comments came just days after a court ruled a class action, led by chuggers against Appco Group Australia, would proceed.

The company is accused of “sham contracting” – hiring workers as independent contractors rather than employees to avoid paying them the minimum wage and other entitlements.

More than 1400 claimants around the country allege they were paid as little as $5 per hour for up to 80 hours per week.

Johnson has been a fierce campaigner for cancer research and was last year named Victorian Australian of the Year for his work.

In 2013-14 he rode 15,465 kilometres around Australia on a unicycle – a world record – to raise funds for the Garvan Research Foundation.

He and his sister later founded a new organisation, Love Your Sister, which has raised more than $7 million for cancer research.

–ABC