There's nothing wrong with being a member here and not posting your work. We have plenty of members who never post their own work, for whatever reason. That's ok... you can participate here in any way you like. There's no rule here that says you have to post pictures of your work, but in my opinion, if someone does decide to post their work, it's only fair for the rest of the members to be able to talk about it.
Like I said before... if any member doesn't want their work commented on, that's fine... simply don't post your work. But if a member does post pictures, commentary from others is to be expercted, not discouraged!