You are into video. You are into music. Good audio still requires big files, and big files take a long time to download at slow connect speeds. And maybe get to sleep sooner. You are into pictures.
Photos can be big, too.
You want to do two things at once. Like listen to Internet radio while you visit some other Web sites. You are running a business. A fast computer and a fast connection save time and money. You want to host your own Web site, have a server, or so forth.