Favours need to be paid back. This story is about paying it forward.

The Truck guy receives no financial reimbursement for his time, fuel and wear-and-tear, but the helpers are not paying back someone for the help, they are paying forward.

Corruption is where someone is collecting financial gain without a commensurate amount of effort. A contract “Man with a Van” who gets paid to move goods is more able to abuse their role for extortion or corruption than a loose social group of “Bloke with a Ute”.