I don’t know if “care” is the right word. It’s just something extra to talk about during the week, that’s all.
Not much different than a non-championship caliber college football team’s fans caring about their teams’ ranking in the polls. People want to see their team getting their props after big wins and being respected, that’s all.
Eventually, as the season goes on, it becomes an interesting barometer of the caliber of team you’re seeing. Ultimately it all boils down to the playoffs and playoff luck though, obviously.