I still don't get...
How someone decides that another person has no buisness using a given website. The internet is a rather free place, and if you don't own said website, you really shouldn't be able to have too much control over who uses it. If its really a problem, start adding a "no using social networking sites" bit in the sentance that those convicted get. Even then it shouldn't be the responsibility of the site to prevent certain people from using it.
It just really irritates me when people try to push taste and morals on the internet. It has none, and there just isn't a good way to regulate it. People should give up on improving the internet, they just need to keep 2 facts in mind when using it to be safe:
1) The internet is hostile by nature.
2) Assume everyone on the internet is a 60 year old man until proven otherwise.
If anyone wants to regulate the internet, make people get internet licenses, and let me design the tests. Nothing like the American DMV, who will let any 16 year old with half a brain drive (If you can barely pass a driving test while giving it your full attention, what happens when you decide to talk on the phone whilst driving down the highway at 90MPH?)