I am a sometimes poster/lurker.
My thoughts are that all posters are not welcome even though the majority of regular posters say they are. I know some posters have been inappropriate at times and understand that. But other times I feel posters are unfairly attacked when they say something or give an opinion when it is something a regular poster may not want to hear even though it may be truth. This is a turn off to some.
As Pingo just said sometimes folks just have nothing to say when a converstation is not relevant or not interesting to them. I personally am not interested in what someone eats each day/meal or what their pets are doing. I do like when folks talk about a new recepie, new place to see, recent trip or something exciting. So I will skim when I have a chance post a quick note if I feel I can add to the conversation. If not I go about my business.
Just my thoughts and am sure there will be some harsh words even though I mean no ill will.