I don't think it's that big of a deal, except wouldn't you feel better selling your stuff to someone with 500 posts as opposed to 5? It kind of correlates with feedback rating.
I know there are forums with little bars or stars that go along with post count under your member name. Not really my cup of tea, but whatever!
I just get excited when I reach milestones like that...my car is about to reach 50,000 miles and I'm sure it will give me a little thrill when it does
And Just BTW,
I have made 2 purchases from members with less than 10 posts here, and received gread stuff, and a great price! But I know where you're coming from.
I just see a lot of people celebrating post counts... thats all