I think you spend most of that time waiting for pages to load. Granted, a BBS isn't going to have everything, but boards have always specialized in certain things. There are music boards, chat boards, rpg boards, art boards etc., A BBS and the Internet is a totally different animal. The web didn't make the BBSs obsolete, the Sysops did. Both have their place, and offer different things.
People use the board for different things.
I offer guitar tab as one of my main types of files, so I get a lot of guitar and bass players. Some people like to read and write messages and prefer to talk to other people in their area. They also aren't spammed via email if they post a message on the bbs. Almost everyone likes to play door games. Legend of the Red Dragon is the most popular.