She had access to the cash register system, which could be used to load money onto gift cards for customers.
"Over a period of time you collected 78 Bonfire gift cards valued at $18, 496.25 ... the remaining money was a further six gift cards worth about $1200."
In total, she stole $19, 696.25 worth of gift cards, leaving the supermarket out of pocket.
According to a probation report ahead of Te Puni's sentencing, she said she and her partner were having trouble making ends meet.
"You saw this as a means of achieving a lifestyle that you wanted to achieve," Judge Grace said.
The offending was "quite deliberate and calculated" and Te Puni was "in a position of trust" at her workplace, which the judge considered aggravating features.
He appreciated she was having trouble with supporting herself financially, "but this wasn't the way of going about sorting that out".
However, Judge Grace said Te Puni had accepted responsibility for the offending and was now back in employment in a different area.
"You made known your situation to your employer and that must be to your credit ... it takes courage to actually own up to things."
Te Puni's new employer is willing to support her through her sentence, the judge said.
He sentenced her to six months of community detention with a curfew of 8pm to 7am daily.
He also ordered her to pay the full amount of stolen money in reparation.
