User blog comment:IamJakuhoRaikoben/Chapter 375: Supernatural, Review./@comment-24446496-20140314165811/@comment-5840892-20140314172640

Because Lucy is 2nd most useless character in Fairy Tail (after Happy) and is good for nothing more than Fan-Service. And everyone is tired of seeing the blonde bimbo naked anyway.

Plus, Lucy has had her share of incredible fights and wins over the series (I'm not so much a Lucy hater to deny that), she beat Angel, she beat the Tentacle monster in Edolas, She beat Rel-I mean Bixslow in the Battle of Fairy Tail, and she beat one of the Enforcers. She would've obliterated Flare were not for Raven Tail cheating.

Whereas Wendy-chan has only had two major battles on her own. She and Chelia fought in the GMG in one of the best damn fights EVER in the series, and it ended in a draw. She fought one of the Enforcers and destroyed the bitch. But other than that she hasn't had the spotlight much, unless you count her very incredible and cute presence.