I think the two major factors for me is that:
1) At this point in life (age 41, retired) I do it as a hobby for me and my immediate friends. As long as things meet our needs, then it's all good. I don't create websites and then advertise them on the web.
2) Currently, we're running a feww zetaboard for our little group. There's four of us. It's horribly slow and buggy though. We tried using vbulletin on my own server, but it's huge in terms of css, js, and image use. My little 368 upstream couldn't handle it.
You guys both have excellent points, but for me, they kind of don't apply. I have no need for link tracking, ads, rotating banners, wysiwyg things, or even the usual visual fluff that goes into a site. To tell you the truth, I even considered writing a desktop app for it instead, and enabling the TCP protocals on my sql server, and I may still do that as an alternative.
I like the web. But like most things, it a mixed bag for me.