Hmmm... Jeff, I wonder why it bothers you.
To enlighten you, I will tell you why I answer questions here... it brings me business, sure, but it also keeps me "in tune" with what buyers and sellers are thinking - things they are afraid to tell me or ask me outright. That's why people like you go to the internet, right? Anonymity?
This way, I can address the concerns of the live people I am working with, without them having to figure out how to tell me their concerns. It increases their comfort level with me.
I check Trulia for questions within my region daily - I try to do it in the morning and evening, like when I check my email. Occaisionally, when there are not many questions in my region, I just cruise the questions from all over... and it is interesting to find out what's going on in other markets. I've also connected people in other states... I am in VA and have connected agents and buyers in California and New York (where most of the consumer use comes from), as well as a few other areas. It's great having strong business connections across the country and exchanging information and tips, it allows me to bring the best of the best to my clients and customers. It helps keep me educated on true market conditions... as the headlines on the news do not tell it all, not even close.
I answer many questions first. While I'd love to answer first everytime (increases my visibility and increases likelihood of generating new business), I simply don't make it all the time.... but like I said, my real goal is within 24 hours.
Are you just sick of hearing from the same agents time and again? Like a prior poster said, I usually don't answer once there are 5 or more answers... by then it's probably all been said.
But, I hope I've given you examples of good reasons that professionals - even busy ones - would be on this site. Having explained that, I work primarily by myself and don't ask my assistant to do this type of work (it would take away the benefit I most enjoy of this site, the education). But, looking at this strickly as a lead generation opportunity, there are agents with teams that make this a priority. It may look like ONE person is answering, but it is a team... all designed to generate leads to that team. I understand it. I don't desire to do business that way personally, but I get it.
Hopefully you get it now, too... and it makes more sense to you.
Despite the self serving goals of the agents here, please understand it is not by accident that most of us are giving the very best advice we can and doing our very best to help people, even though we know the vast majority of times it will NOT bring us business. We are the agents that are choosing to focus on generating business by helping people and hoping they'll be impressed enough to use us for real business; instead of flashy marketing campaigns and/or cold calling. I don't see anything shallow or negative about that. I hope you don't either.
My daughter said it best (she's 5) when she told someone what I do - "My mommy sells houses, helps people and makes new friends".