Thank you JIMWORCS..
I just saved the sheet while buying the ticket which said compare fare types. Luckily, I found it on my computer.
(if you do not see the image, please right click and open in a new window)
I did not get any other mail from them regarding "fare rules". I am sure Etihad will come up with some explanation for this. Like, the customer care rep said- "it is only for reference, and it is not true all the time". My point is, how can you put in such a neat format, the fare types, and then, when it is mentioned in your ticket that your fare type is Economy flexible, how can it have different rules. Is that not cheating?
Here is the copy of my ticket
(if you do not see the image, please right click and open in a new window)