We need to see the age at which the vaccinated children are still getting the pox. That makes all the difference. This is a mild(er) disease in elementary age. Even only 80% of the disease in the older years (teen and adult) is far worse.
Exactly. That's why it's so important for every child to get the vaccine. If you go unvaccinated, the likelihood of you getting chickenpox at an older age is much greater, now that the disease is much less prevalent. However, I think many states are now making the vaccine mandatory. Post #4 illustrates why you don't want to get chicken pox as an adult...