"Blood money" isn't buying into a stock which you think will go up because of a disaster. "Blood money" is working for a credit card company and setting people most badly affected by the disaster so they will never be able to get out from under the interest and penalties. Blood money is selling gas at a high price when you know next week the gulf will be almost totally operational again. "Blood money" is being a part of the media and selling fear to promote your ratings during a disaster hoping people will watch your station because you've exaggerated the most and they will be hooked and watch you after the disaster is over - increasing you advertisement income.
I could go on for pages. It depends on what you do with the money you make on stocks which will go up because of the disaster. Who are you taking money from? The victims of the disaster or those who are in a totally different and comfortable position. I don't think the victims of a disaster would be trading stock.