No, it's good that you brought it up in the event that something 'shady' was going on. By calling attention to what could have been something illegal it not only sends a message that unscrupulous doings are not going to be tolerated here but also may help prevent behavior that could concievably close down this site because of illegal activity. If the individual trying to 'flip' the item was actually an FFL, then they will understand and support your questioningI thought about it, but didn't want to be 'that guy'. Again, if they have an FFL, what they are doing isn't wrong.
update:
It looks like the ad is no longer there now, so I'll go back to my hole and be quiet. Forget I said anything!! lol