The incident took place at Hackham IGA yesterday afternoon, when a man allegedly refused to pay for the goods he’d gathered.
“He was screaming, yelling, abusing all the staff,” owner Baggio Wang said.
One staff member, a 15-year-old girl, was reduced to tears.
A shopper approached the man and tried to get him to leave.
The pair wrestled, with the shopper eventually having his shirt torn off.
He ran into the back of the store and emerged with a machete used to cut fruit, chasing the alleged robber and a friend out of the store.
Mr Wang said the shopper was “a really nice guy” who had been in to buy some Mother’s Day gifts.
Police are investigating the incident.