It's harder to get free stuff, these days. It used to be you could go to some event and someone would hand out free shirts, but today you have to go through the trouble of giving blood.
I always try to give blood when the blood-mobile shows up on campus. It saves lives and I am impressed at the people I see there. I have never given blood without meeting people in line who are terrified of needles but have decided to overcome this in order to help. It would be easier for these people (mostly college students) to sit in their dorm room or hang out on campus, but they serve others by going through the excruciating process of facing a needle. It's not bad for me, but when I see what some of the "needle-phobes" go through it causes me to admire them. (I'm always tempted to tell them that the needle is really really big and hurts a lot, but they are going through enough.)
This time around I learned that the person who draws blood is called a phlebologist, a term so obscure you can't find it on Wikipedia. I didn't know that.