I agree this is part of the problem Baba.  But i'd go a little further and suggest the trading share count for some is much higher (~ 20k -100K), with the selling perhaps even coordinated by a few.  As you point out it doesn't take much to quell any sharp rises. 

We are led to believe some shareholders hold millions of shares.  Yet we see repeated vitriol toward management (who from my vantage point are doing a great job) from certain quarters. Usually at the most precarious of times.

Is it lucrative?  Not in my estimation, as the profit is too small 

I'd kind of diagree with this.  But I suppose it is a relative concept to the individal.  Considering the amount of times this has risen, then fallen over the years.  If you rinse repeat on a number of occasions you could end up with, either lot's more shares, or the removal of your original investment capital risk.  Consider also that they may own lots of warrants, the risk is then minimal.