Eric Messick reunited Noelene Straker with the $50 note she lost at the BP Station on Ulster St on Saturday after he picked it up in the petrol station shop. She thanked him with two Jim Bean cans.

A BP customer who reunited a "little old lady" with her lost cash says he was made to feel like a criminal for not wanting to leave the cash with forecourt attendants.

Dr Eric Messick picked up a $50 note on Friday afternoon from the floor of a BP Connect store in Ulster St, in Hamilton's northern CBD.

He said staff threatened to ring the police on him after he found money on the store floor, asked if it belonged to anyone, then opted to leave his details with BP staff, instead of leaving the note.

"I picked it up, right away looked around, went over to the attendant ... then she basically started having a go at me. There was definitely a 'how dare you'.

"[They] made me feel like a criminal."

Messick said he took the money home because an attendant told him it would go into the BP till if it was unclaimed.

The note's owner was Hamilton woman Noelene Straker, who was reunited with her money on Saturday after the station passed on Messick's number. She said it "seemed a bit strange" that Messick took the note, but understood his reasons.

"But soon as I rang him up [on Saturday] he said I'll come around and drop it off, and it was the same $50 note, so that was the honest thing to do.

"The BP Station said to me that [Messick] was a w..ker, the way that he was behaving. What a bloody drama."

Straker said she was grateful for Messick's honesty.

"I'm not that financially well-off, so I gave him a couple of Jim Beam cans to say thanks."

The Ulster St station denied this, and said any lost property went into a safe in case its owner returned.

An attendant at the station, who gave his name only as Bevan, said Messick was asked to leave the note with staff, after they reviewed CCTV and identified "a little old lady" as the person who dropped the note.

"He refused to, and that's when things got a little heated," the attendant said.

"We had no clue if the name and number he had written down was legit, that's what we were worried about.

"I think anyone would have questioned it really. He didn't say how much it was, just said I'll leave you my number and get her to ring me if she comes back."

Messick, a registered psychologist, said he'd been a regular customer at the station for 15 years and thought the morning staff were "lovely", but the incident meant he would no longer shop there.

"I'm not going to spend money somewhere if they treat people like that."

Messick said he'd returned an envelope with about $2000 cash in it to "a hysterical woman" about four years ago after he picked it up at Waikato District Council.

"It was right next to my car and I thought, oh my. It was somebody paying their rates."

Hamilton Police Inspector Jeff Penno said police were not allowed to confirm if the BP station reported Messick.

"That is a breach of his privacy, I can't tell you that."

