Stats are incredibly useful in the hands of the designers themselves. Quite necessary, even.
However, I also think the obsession with stats is poison to the wider player community. The knowledge is given with the intent to do good; but in reality, it's only ever used as a vehicle for senseless outrage and vitriol. You have players complaining about lists that don't really exist outside of tournament top tables, about armies they never play against, and about scenarios that have been literally concocted in a statistical laboratory.
It's all meaningless to the average dude or dudette playing games at the local store--except as an excuse to carp about things they heard on the internet.