I've stumbled upon it in Flann O`Brien's book "Third Policeman" and cannot figure out the meaning of the chip packet phrase. The context:

I had never seen the old man but knew all about him. He had spent a long life of fifty years in the cattle trade and now lived in retirement in a big house three miles away. He still did large business through agents and the people said that he carried no less than three thousand pounds with him every time he hobbled to the village to lodge his money. Little as I knew of social proprieties at the time, I would not dream of asking him for assistance.

‘He is worth a packet of potato-meal,’ Divney said.

‘I do not think we should look for charity,’ I answered.