Castration, Incarceration or Incineration

The title of this post is the only ways to deal with child molesters.
Why aren't drunk drivers, murderers, drug dealers, con artists, and shop lifters made to register with local authorities once they are released from prison but child molesters are?
Maybe it has something to do with the fact that police know that sex offenders will strike again and they want to keep track of them when there are abductions and attacks such as the case in Florida with Jessica Lunsford. It is no coincidence that the guy who raped and killed Jessica Lunsford was on the national sex offenders list, and it's no coincidence that the list is the first place police look in these types of cases.
My point is this; if everyone knows these assholes are going to strike again, why let them out of jail? Obviously putting them on a list does not stop them from committing these crimes, it only helps us catch them when kids come up missing. Great, a lot of good that did for Jessica.
If we know these types of offenders are typically repeat offenders, then why not nip it in the bud, or I guess, nip their balls in the bud. A sex offenders list does not protect anybody!
These types of people should either be put in jail for the rest of their life, castrated or shot.
John Evander Couey's long criminal record includes indecent exposure, burglary in which a girl was fondled in her house, carrying a concealed weapon, and the charge that got him on the sex offenders list of fondling a child under the age of 16. This guy is obviously a sicko and always has been. Can anyone give me one reason why he was living freely among us? What possible benefit was he providing society?
Here's a good policy; let the guys who kill kids out of prison but make mandatory sentences for people who do drugs. After all, we must clear our prisons of child rapists and murderers so we have room for those dangerous guys that have over 100 marijuana plants.