I'm gonna have to agree, like.. I'm not opposed to watermarking much. But there's obviously large sections you could put this mark in that doesn't go over the text you're reading (or attempting to read) or even near edges of picture, it's just slapped on there with a care in the world it seems that it dramatically reduces the quality of the work.
And permanently gets a nice "never go their site" note added, if do this type of watermark, can only imagine the ad-warfare & pop-up battles the site would inflict. (no haven't checks, nor will I)
And salt in the wound, lets skip 12 chapters! IF others have it, especially MUCH further then posted, they obviously are not going to, and have given up any "right" of being a group uploading.