why consolekit & policykit & elogind?

Hi all! This question might be a bit OT (and probably totally useless for the systemd-fraction), but ... what is the purpose of need consolekit & policykit & elogind ? I observed consolekit creating hordes of children, resulting in ~ 5% cpu usage. I deleted consolekit & policykit & elogind, restarted the system and found everything still working perfectly. So, what are these good for? Is TDE depending on these in any way? Nik -- Please do not email me anything that you are not comfortable also sharing with the NSA, CIA ...