They are supposed to.
Here is a very enlightening article by a Game Designer named Raph Koster. The most important thing Designers need to realize is- The Client is in the hands of the Enemy.
Another important thing Developers need to realize is that-
I wonder if Yoshi and Co. have read The Laws of Online World Design.Macroing, botting, and automation
No matter what you do, someone is going to automate the process of playing your world.
Corollary:
Looking at what parts of your game players tend to automate is a good way to determine which parts of the game are tedious and/or not fun.