gksu vs other authentication programs

view full story

http://askubuntu.com – I've found that most of user authentication programs that used in Ubuntu is not gksu, but it's not a problem. Problem that these programs do not lock the keyboard (while gksu lock it). Program xneur (analog puntoswitcher) can log key. And when I turn on this option, I found my password in this log. Why is Ubuntu so far used such an insecure method of authentication? I understand that no viruses in Ubuntu, but why provoke it? (HowTos)