I'm your traditional dork, I've never played sports, feared gym class in my school years, and never watch pro games on tv. I hate football with a passion.
However, I personally enjoy pre-16-bit sports games, mostly baseball.
Old sports games have a simple "pick up and play" action/arcade quality to them that I like. You don't have to be into real life sports to enjoy those games.
Today's sports games are far too complex for a geek like me. Worrying about stats, talent rosters, managing, complex plays, and deep knowledge of game rules.
Granted, modern sports games are very deep&interesting to people really into sports, but I don't fall into that category. They're simply complex math to me that I'll never understand.
For me, when it comes to sports games, it's, "keep it simple stupid".