Why are items automatically purchased for me?

In every game items are automatically purchased for me throughout the game without me adding them to the quick buy area.

The behavior is as follows:

1. Game starts.
2. Items are automatically bought. The items include the Donkey courier thing, a town portal, some tree eating potions, and some kind of dust that I can't remember the name of.
3. As the game progresses, additional items are purchased like the invisibility pendant and more potions.

It completely destroys the ability to buy any meaningful items and puts me at a serious disadvantage. I've gone through the settings and don't see any auto-buy new player setting.

Any idea why this might be happening?

Solution 1:

I found the setting, but I'm not sure how it got turned on as I chose expert or whatever the highest level setting was. Switched that and then everything got better.