Making realistic looking textures is hard as fck and time consuming. With "16 bit style" you can appeal to the "good ol' times", get nice graphics working, and you're good at it, get an artistic result too.
There seems to be an ongoing trend with indie devs to go with a pseudo 16 bit art style when approaching game developing. Is there a particular reason why they choose to make this style, or is it a design choice?
Its the natural result of resource constrained development, you try to make the best of what you have.