1) People pay the fraudster for "discounted" food.
2) The fraudster places the order using the stolen account.
3) The fraudster tells the people who paid them: "Go to the pub car park at 9pm and wait for the Deliveroo driver. If he asks, your name is John Smith."
4) Profit.
it's also pretty hard to imagine it's worth the effort, you still need to advertise so people know about your service! the service would have suspiciously similar dishes advertised in menus corresponding to original restaurants etc... the unsuspecting customer gets to open the door for a Deliveroo person! there's just so many ways this would go wrong in the real world that it doesnt make sense to invest time and effort in MitM'ing Deliveroo from a limited set of compromised accounts...
This all indicates the fraud is happening from within Deliveroo
Why would they ever sell it at a loss? Everyone needs food, so they get the value by consuming it themselves.
Not even that hard to investigate because there’s a complete paper trail after a fraud is reported of what was ordered, who delivered it, and where it was delivered.
That's how the cop would describe it of course. Anyone with half a brain knows they always throw the book but the whole book never sticks.
What sticks will probably wind up being some sort of fraud and the punishment will probably be something like fine and probation.
To me all this suggests the fraud is happening within Deliveroo, at a level above the delivery people.
The only credential fraud outside of Deliveroo I can envision is if the black hat hackers contact the restaurants to conspire, the food is then never made but the profit is shared...
Eat it.
When I was in college if the pizza guy was in the lobby (invariably trying to call someone who wasn't picking up their phone) very long it was customary to ask him what he was delivering and buy it if you wanted it.
What they may do is:
Order items that aren't as perishable such alcohol & ice cream (e.g. Ben & Jerries) and then resell those via partner off-license shops.
This is how the market for stolen gas works anyway, I'd imagine stolen cola and beer would be similar.