After seeing the amount of gil spammer and I saw someone in our party all of a sudden got 500k gil, I was wondering how does SE actually know if someone brought ffxiv gil or not? Do they see a player all of a sudden have a lot of gil and ban them? Or does someone have to report after seeing it?
Its unlikely they will be found out, to be honest. I guess its possible, but you can be guaranteed the ones shouting aren't the ones botting.
Through bots, you can control gil flow through the AH, and move gil around by making legit purchases of overpriced crap with the characters that move gil.
Through degrees of separation, the gil can become mostly untraceable. All that needs to be done is a gil seller friended and then gil received by mooglemail.
MMOs dont punish buyers, only sellers. The reason for this is nobody can prove you bought gil. You could claim it was sent in error. If they DID ban for buying i know a few characters i would spend $5 on to get them banned.
Eve Online resets the wallets of currency buyers but not after one time. They flag any account with big transfers and if they haopen a lot then the wallet gets reset. This results inthe nearly irreversible negative wallet situation which you can google for more information.