What benefit do people get from looking up info on the registry? I ask this out of genuine curiosity. I think it's a good thing to have the information available... but, then what do folks do with that info?
I think that if an offender lived within a few blocks of my house I would want to know about it, especially if I had small children. Otherwise, who knows, I might unwittingly hire the person as a babysitter or something.
But knowing that a bunch of offenders live within a 20-mile radius, or whatever the map shows, isn't much help, IMO. In fact, I think you can safely assume that if you live in a heavily populated area there will be some offenders and other dangerous people living somewhere around you, whether you can find them on a website or not. I can't think of a situation where detailed information about specific individuals would be all that helpful. Unless maybe you have some direct involvement with a person you are concerned about, and want to check on his/her background.
BTW, I realized after posting that the reason I have no offenders living in my immediate neighborhood is probably that my immediate neighborhood contains an elementary school and a middle school.
Also, coincidentally, my local paper today ran a story about sex offenders. In the comment section, some people pointed out that "sex offenders" can include 18-year-olds who date younger teenagers. And one commenter posted that s/he has a friend who was arrested for peeing in someone's yard while walking home from a bar. Apparently, at least in that person's community, that qualified as indecent exposure, thus a sex crime. So the hapless urinator is now classified as a sex offender and has to register, introduce himself to neighbors as a sex offender, etc.