This tactic is used often to “give the people something to do”. Remember the blood drives after 9/11?Not only are people dumb and indoctrinated, but it made them feel somehow like they were the smart ones, keeping themselves and others safe by wearing a mask. The Left loves nothing more than feeling smarter and more virtuous than the rest of us.
BTW, my understanding is the vast majority of blood donated is not used in lifesaving transfusions as most people assume happens. What they need is the universal donor blood, the rest is sold or otherwise distributed and even disposed of when too much of it is donated.