Thackney, for better or worse, the public school has become the surrogate the state mental hospital. Children who were once institutionalized are now attending school with your children. Unvaccinated, these challanged children are at significantly increased risk of both having Hep B and passing it on to other students in the schools.
Another thing to consider is that some vaccines provide lifetime immunity, the Heptavax appears to be one of these. By vaccinating children, you are protecting them from exposures later in life, at a time when they are unlikely to be seeking medical care otherwise.
It sounds like the same arguement would hold for HPV.