The judge said Rongonui had been "very much the primary offender" and Naera had effectively been charged as a party and had received no benefit from the robbery. Rongonui had already been ordered to pay the entire reparation.
Rongonui had seen the woman leave a nearby bank "carrying a quantity of cash".
After following her, he met Naera and the two followed her on her mobility scooter.
At the council buildings Rongonui followed her inside, while Naera stayed outside with the car engine idling.
Rongonui then "ran up and grabbed the handbag" and ran back to the car, which left at speed.
The judge said by his guilty plea Naera had accepted that "at least by driving away at speed" he knew something of this nature had been committed.
Judge Harrop said Naera had recently become the father of a young baby with "significant health issues".
"I don't think the community is served at all by you being sent to prison."