So i read the whole first page once and for all, but i still don't get much about the event.

I understand that we make a deck of 5, and then fight another player who we select from a small pool given to us everytime we do a challenge.

Now what i don't get is, what purpose is there in all this? I know we beat opponents for rewards, but are there rewards for the player who defeated the most during the event or something? Is there any reason to actually defend yourself when you, according to the first post, don't lose ANYTHING on it?

Basically, please tell me why it is important for some to use trap decks and similar. I can partly understand this if it means that you get more rewards from winning when defending, but is there any other reason?