When Is Too Much Information Too Much Information

Why people consistently put information on Social Networks (Facebook, Twitter etc......) that can lead to jail, prison or worse. For example, why would you put pictures of yourself smoking a joint or snorting cocaine. What would it take for us to get the picture that what you say on the internet can be detrimental  to you down the line. To be more direct and to my point Facebook is getting ready to launch a new service called Places.Basically it tracks your every move and display your location on Facebook. How will this benefit  you? Do you really want people (friends or not) knowing your every location??  Its becoming too much.."Too Much Information"