You're paying for a lot more than just the hardware your instance runs on with EC2. You're also indirectly paying for the other systems they make available to you within EC2 (auto-scaling, ELB, EBS, CloudWatch, etc).

If you don't need these additional services, AWS is indeed a bad value. If you use a good chunk of them like we do, it's money well spent, though it won't fit neatly into graphs like the previously mentioned one.