Definitely a fair question.Let's broaden the scope of the question so as to step on everyone's toes: Is this a normal and accepted practice of the Christian? If the work of the minister is to prepare you for the work of the ministry, shouldn't we all be as equally busy doing His work?
Is there a different standard for "clergy" than other "normal" followers of Christ? If so, is that a biblical concept or just something we've created by which to judge another?
BTW, I'm not a pastor either (though I do preach on regular occasions), so I'm not asking this as a defense, just something more to consider...
I will counter that the average christian is not given a flock to tend to, though. Knowing my pastor, he is so busy that we had to hire another administrative pastor to take on some of the load. I couldn't see him having the time to post something hourly over the course of 6-7 hours a day on a board like this, or numerous posts consisting of many paragraphs taking substantial time to think through and post...and if he did, he would most likely link the BB to our church website.