Yes those non-posters are suspicious. I guess some of the attractive prizes might creat a honey-pot situation. A fair few of the winners do have 0 posts
. I can't think of any reason this would be, other than people registering solely for the comp - presumably entering LOADS of times to ensure a win too? (surely people aren't name changing just for the comps?)
Maybe you have to have had x number of recent posts (within last 6 months) to qualify?