I know for mustachians, it's just another metric that's fun to watch, but one of my co-workers is obsessed with hers and believes it really buys her something worthwhile. She seems to use the "my credit score is great" as an excuse to spend money on silly items. As far as I can tell, it must only really count towards mortgage or car loans.
Anyway, yep, it's fun to see when it's free on a statement, but I've rarely gone out of my way to find it.