you end up on the fraudster list and it will follow you for the rest of your life
(CIFAS in the UK)
and then if you tell them it's not you doing the transactions: you will be immediately banned
"oh it's my agent" will not go down well
Also, at best, you can only add to the system prompt to require confirmation for every purchase. This leaves the door wide open for prompt injection attacks that are everywhere and cannot be complete defended against. The only option is to update the system prompt based on the latest injection techniques. I go back to the case where known, supposedly solved, injection techniques were re-opened by just posing the same attack as a poem.
The courts have an answer for this one: intent. How do courts know if your intent meets the definition of fraud or theft or whatever crime is relevant? They throw a bunch of evidence in front of a jury and ask them.
From the point of view of a marketer, that means you need be well behaved enough that it is crystal clear to any prosecutor that you are not trying to scam someone, or you risk prosecution and possible conviction. (Of course, many people choose to take that risk).
From the point of view of a victim, it's somewhat reassuring to know that it's a crime to get ripped off, but in practice law enforcement catches few criminals and even if they do restitution isn't guaranteed and can take a long time. You need actual security in your tools, not to rely on the law.
It probably also violates local laws (including simple theft in my jurisdiction).
You said please give $500 and they gave $500. No crime here, officer.