After the man's passing comment, Weepu began yelling abuse at him.
She then ran 20m to where the victim was and pushed him forcefully in the back with two hands.
The man was launched onto the bonnet of a car where he hit his head and then fell to the ground where he again struck his skull on kerb, knocking him unconscious.
"You weren't done," Judge Phillips said.
When the victim came to, he found Weepu in his face, gripping his collar, shaking him and swearing.
The court heard the pensioner suffered cuts and bruises and the head injury resulted in him losing sight in his left eye.
"She could have killed me," the man said.
The man's eyeball was ruptured due to the force of the blow, the judge said.
Weepu initially told police she was not even in Dunedin at the time of the assault but later pleaded guilty to injuring by an unlawful act.
The victim was out of pocket by $500 but the judge said he could not order reparation because the defendant was penniless.
Earlier in 2015, Weepu had also unlawfully used a bank card belonging to another elderly victim.
Despite having no authority to use his money, she used the card "all over the place", the judge said.
While on bail, the defendant faced further charges when police received information that led them to her house.
There they found a purse hidden in long grass containing cannabis, a glass pipe and a small amount of methamphetamine.
When police put the items on a table and questioned Weepu, she grabbed them and fled before threatening police with a rock when they ran her down.
Most recently, in April, the defendant drove away from a Balclutha petrol station without paying for $56 of fuel.
Taffs said Weepu's dysfunctional upbringing meant her blooming criminal record was unsurprising.
"She's not been brought up in a home where there have been appropriate moral and disciplinary guidelines of any sort," he said.
"Criminality and drug abuse his been a constant social background to her upbringing."
Weepu was jailed for two years three months.
