"If you really think that we're talking about "peadophiles and rapists," you're not paying attention."
No, it is you who hasn't paid attention.
"There is no centrally held register of sex offenders in the UK, but the Home Office says the system of notifying the police is commonly known as the sex offenders register." (source: BBC news - http://www.bbc.co.uk/news/uk-12476979).
There is no official sex offenders register in the UK. What we are referring to here are people who have served 30+ months in prison for serious sex crimes, and have to register with the police every day for the rest of their lives. There will obviously be failings in the system and people will have to be on the 'sex offenders register' when they don't deserve to be, but Mr. bicycle shagger, and people who 'take a whiz' in the middle of the night are unlikely to have served 30+ months in prison for their crimes, are they?