its not a good habit for those who are facing this problem... but its a good habit for those who uses this normally !!!
if these people are really doing this to get more and more details about a person, then its fine... but if someone is doing to specially someone, thats annoying...
but due to this habit, we can not suggest that to avoide such type of friends, cuz every person must have at least one bad habit...
so if he has a habit which is annoying for you, he must have other habits that you like as well...
so my suggestion is to be candid to such type of persons, and when ever you feel that you are uncomfortable... just say candidly/smartly NO ANALYSIS !!!