It's the same method employed for any rule violation in order to make it less likely for someone to identify and go after the individual or individuals responsible for filing a report.
Furthermore attempting to bypass the rules through workarounds often still counts as a breach of the terms of service. If someone creates a character name that reads as a slur with has a few letters adjusted to technically not be on, it can still be considered inappropriate and forcibly changed.
So, too, would it be viable in the eyes of many for someone to be punished if they're advertising their venue as suitable only for players aged eighteen and up when a little bit of light digging reveals that escort services are on offer in exchange for gil.
A lot of people seem to be under the impression that such is allowed so long as they aren't caught doing it - but if they're not keeping it entirely private, then the risk of exposure is naturally higher.
I'd also note that GM's are capable of examining chat logs at length and it's perfectly possible that they identified something worthy of punishment.