Facebook is not the problem, users are. Back in the day most users would not even share their name on the internet and now most people are doing the complete opposite: They share way to much without thinking about what can happen.
If you don't want a person to see that you are online, just remove the person..or even better, don't add the person in the first place. If you join a service made for sharing personal data you should at least think about the consequences.
> Facebook is not the problem, users are. Back in the day most users would not even share their name on the internet and now most people are doing the complete opposite: They share way to much without thinking about what can happen.
Facebook is indeed a major part of the problem which you just described. They hold a 'real name' policy, and have well-crafted call to actions which pressure people into feeling obliged to share information. The entire service is designed to mine data from you, which is a bonus for a stalker.
Though I don't feel your suggestions - 'just removing or never adding them in the first place' - is a bit moot when the author has described exactly why the person is on their list..
If you don't want a person to see that you are online, just remove the person..or even better, don't add the person in the first place. If you join a service made for sharing personal data you should at least think about the consequences.