Members with 0 posts & password thieves

I played in a forum game tonight. Most of the players I know from another forum. They just started playing here a couple of months ago. I checked the member list starting in January and none of their names were listed so they must be password thieves. Does anyone here care?

There was one player who's name I found who joined on May 20th and has a total of zero posts. Looking thru the list I found many members with 0 posts. Shouldn't we drop these people from the forum? Shouldn't we also try to have the password theives ban from the sites we have our games at?