Interestingly, I also think we have as situation where we're sometimes looking for 'fake looking' CGI, and filling in the fakenes ourselves on a subconscious level. The thing that springs to mind is the locking mechanism near the end of Indiana Jones 4. I remember being pretty disappointed at what I thought was shoddy CGI work on that when I saw it at the cinema. It was only months later that I saw the making of, and found out it was a practical effect. Sometime knowing (or just thinking) something is CGI is enough to blow the effect, when actually it's more than adequate.