Hunz, the $1 doesn't refer to registration fee.
Services such as drop.com.au and netfleet.com.au complete to "catch" domains that drop by hammering the registrar at the exact time they become available. People bid on domains with them for the privilege of them trying to register the domain on their behalf. There is a lot of info elsewhere on the forum re this.
What is being referred to here is a bid of $1 (obviously very low) plus normal registration fee.