Is it normal to not care?

On Facebook everyday there's posts that have a picture of some poor sick person, many times a kid with cancer or missing limbs, autism, burn victims, mental retardation, etc., etc. ad nauseum with a caption that says something about "like or share if you care, ignore if you have no heart" or some such similar line.
I see this and think, "haha, nope, you attention whore!". I mean, does it suck that the little baby in the picture has leukemia? Yes. Does liking or sharing the picture do anything? No. Then there's the "share this to raise awareness of ____" stuff. I'm sorry, but I'm pretty sure just about everyone is aware of breast cancer, autism, child abuse, animal abuse, etc. But hitting the like button on a picture doesn't help those people.
So, is it normal to feel this way, or am I just a coldhearted SOB?