Olive oil has a lower smoke point than the other oils you mentioned. As a result, when OO is heated in the pan, it vaporizes and settles on the inside edges of the pan and burns on creating a brownish coating.
Oils like canola, corn, peanut, safflower, etc. have higher smoke points so the vaporization does not occur as easily, resulting in cleaner pans.
For that reason, I don't use OO for higher heat applications. Besides, if you're cooking a piece of chicken or steak, etc, you won't really taste the difference in the oil used.
So I'd say your oil isn't fake. It's doing what OO is supposed to do.