User blog comment:FloaterJ/Nitpicker's Nook/@comment-26131697-20150222152610/@comment-25869525-20150223011458

To what Omega said about blood types when they drain Grounders. Yeah, they could have just shown us them doing that once even, so we could assume they do it every time, but just don't show it after that one time, to not waste time that could be used for more action or some movement of the story. But, they missed that.