This is one more way for them to harass people. You check anything other than "I refuse all", and they will start assuming you are weak in the tower. And, unlike those pledge forms or aux pio forms, you cannot just leave the blood card at home and "forget" it. You will be forced to sign it, and there will be two hounders watching. That is enough so they can "mark" you if you check that you will accept some fractions.
Worse, if they later revise their position, those who checked that they would accept some or all fractions will be rounded up for houndings. They will be watched in more areas since, if they are less than total in this, they are going to be less than totally strict in other areas (like missing meetings, field circus, and their entertainment). That could make a witch hunt easier.
Not to mention confusing some medical teams. In an emergency, anyone that is willing to accept some fractions but not others will face confusion that might delay critical treatment. And, if someone refuses any fractions at all and the doctor sees another patient that will accept some or all fractions, that is going to create additional difficulty. The doctors will wonder why a patient will accept one fraction but not another, and that could delay treatments.
I say just accept the blood if the total cost exceeds the total benefit. You must weigh the scarcity of the blood, risks of complications, and the money cost against what it will do for you. I am against a stupid blood transfusion (that is, one that has little or no benefit) because it wastes blood for critically needy patients and there is the risk of complications. But, if your life and/or limb is at stake, for sure the risks are worth taking.