What we really need is a right click > report function.

/blist doesn't alert anyone to gil sellers, it just shuts them up for as long as it takes them to make a new character and start spamming again. Square-Enix needs to implement a way to track these parasites for every time they interrupt a legitimate player. Letting us report them with a click (rather than the clunky and tedious harassment report that's the only in-game option now) would quite handily take care of this.