I don't know. My guess is because someone else has one. I don't have a lot of room to talk. I have one, too. Here's the reason the pages are so darn technical.
Counters are technical.
It's a fact of Internet life. This is a little program that sits deep in the guts of an Internet server and does tricks like make an Image Map work or count the number of visitors to your page. The highly technical pages on counters assume you have the ability to get into the guts of the server and place a CGI application. My guess is that if you're reading this, you don't have that ability. You simply want a counter on your page.