Part 2/2:

"You don't play my sub." FFXIV has very rewarding and engaging crafting, gathering and market systems that are absolutely amazing when they work. Market bots significantly detract from all of these systems by devaluing the time that players spend engaging with these systems because they significantly reduce a player's return on their time invested. Market bots are also involved in RMT, which damages the game's health as well as contribute to organised crime such as credit card theft which ties to other serious crime such as identity theft: see the bots which send phishing links via tells, blackmail, hacking, use of ransomware etc. as well as any other criminal activity that the proceeds of RMT can fund.

Now how can SE go about attacking the MB bots? Firstly they could set up checks that would alert them to trading activity that doesn't fit the profile of a human player (even a dedicated one), such as 24 hour activity, high percentage of items being traded as a third party source, and consitent timings of price adjustments. Now we know that SE can't look at what applications are running in the background of a user's machine, though there must be a interface through the client that thrid party software can interact with. Rewriting this interface to eliminate or frustrate attempts to automate the selling of items would also detract from the ability of market bots to function.