The difference is that those who see the fairground mirror reflection definitely know it is so twisted that it can not be real, so no deception there.
The twisted reflection is a "real" image and no reflection is the "real" object.
The real deception with mirrors is...
The real deception with mirrors is that they show a mirror world where left-is-right and right-is-left.
1. Calm ocean does exist
In that case, you shouldn't claim that you were being deceived when shown a photograph from which a person's image had been removed, or shown a photograph to which a person's image had been added.
After all, situations did exist where that person was not present, and situations did exist where that person was present.
2. We are culturally conditioned to understand that camera captures certain moving objects as blurred
So Big Stopper images do deceive people unfamiliar with the motion-blur that has become accepted in this culture over the last 30 years ?
3. It is too obvious that a filter/trick was used, thus no deception
It's only obvious to those who've already been shown the trick -- after all, "Calm ocean does exist".
What's obvious to a photographer is not necessarily obvious to others.
For example, if how different lenses effect our perception of depth in a photo was generally obvious, that would not need to be explained in every Beginning Photography