Recorded this video of a bot farming in FFXIV. Notice how he stays below the surface of the ground and has stealth mode on and teleports between farming locations. Be sure to report this activity to SE via the help desk system in-game on the main menu.
As someone who recently started gathering items, I find it very frustrating to come across a number of cheaters while on my travels who are able to gather thousands of items working around the clock where I only get a fraction of that in my short time playing. This means they can flood the market with lower-priced items which makes it very difficult to make a profit for a gathering class such as a miner or a botanist.
This also means for every bot out there gathering, some account is getting all the items and selling mass numbers of items for a huge profit, when they then try and sell on websites for real money. This type of activity is illegal both for accounts selling the gil and accounts buying the gil using real money and players can be banned for using such sites.
While this is just a small example of what goes on in-game and the SE team are working hard to eliminate botting like this as well as other threats to the economy and gameplay, I ask that players stay ever vigilant in their efforts to report illegal activity.