The situation regarding factor VIII is not completely unique.
Albumin for example is also transfused in 500ml units just like PRC's and Plasma This is standard treatment for burn patients. In fact, a patient with severe burns could easily require 10 - 15 units over the course of several days.
JW's permit this treatment, which is something of a paradox: What is the difference between one JW patient voluntarily connected by IV to an inverted 500ml unit of 5% Albumin solution osmotically equivalent to normal plasma and another JW patient voluntarily connected by IV to an inverted 500ml unit of whole plasma? You can't even tell the difference between these two liquids without reading the label.
Yet the JW's believe that the latter individual would have broken God's law, while the former would simply be exercising his or her conscience in a "gray area." This is one of the reasons that many in the medical field have such a hard time fathoming the JW position.
Human Gamma Globulin (IgG) may also be transfused in whole 500ml units depending upon the circumstances. With IVIG we are also dealing with a pooled blood product that took thousands of individuals donations to obtain. This is standard treatment for ITP (Immune Thrombocytopenic Purpura) and Kawasaki's syndrome. I've seen this with my own eyes. I've seen the JW HLC recommend IVIG as an alternative to the transfusion of platelets.
Of course, when pinned down, the WTB&TS will claim that they don't officially "endorse" the use of any blood product. But we all know that the reality of the situation is that through their church rules, they actually do.