well, their community managers read the forums then lie to the devs and say, "they really like Lightning!"
i mean, just put yourselves in their shoes. if you were a forum/social network guy working for Square Enix and devs asked what fans are saying, would you go, "o they said LIGHTNING SUCKS! FF13 SUCKS MAJOR DONKEY BALLS!"? they probably just print off the posts made by FF fanboys oggling at Lightning's gun or something.