its fairly normal across internet communities. remember also the read count is a fairly rubbery figure.. its not how many unique views the thread has had. the person posting 3 times in the thread might have viewed it 20 times reading replies.
also a lot of people might be having a quick look during short breaks (work

)
this site seems to index well with google (instantaneous the other night - google analytics?) so, a lot of traffic from there to any page mentioning a product, technique, space object.
but yeah theres always a lot of lurkers. thinking about it theres places i almost never post to. others i probably talk too much