I'm an intentional lurker sometimes. I read things, record them in my brain, and make my theories/etc. I try to switch up my activity and posting styles regularly so no one can have a beat on if I am scum or not for the games that I am.
There should be no issue with being a "lurker", if you get called out for it, respond (or don't), and move on. No need to get all emotional over a forum game.