This misuse comes from, I believe, a lack of understanding of its origin; to wit, the term comes from Hall of Famer Dennis Eckersley.
Eckersley has a unique grasp of the English language. He turns a phrase and then twists it into a mobius strip. Sometimes it gets so bad, you need an Eckersley-to-English dictionary to listen to him speak. Anyone who heard his post-game interviews or his color commentary on Sox games knows this all too well. His most famous piece of phraseology over time has become, of course, "Walk Off" which refers to the act of giving up a game winning hit. But it is the defense that walks off the field after such a hit, not the offense. The offense (usually) comes on the field and celebrates. But to hear most baseball announcers or ESPN talking heads say it, the batter "Walks off" or the home team "Walks off" and that is just undeniably incorrect. Eckersley was referring to putting his head down and dejectedly walking off the mound. When you talk it through, that makes perfect sense, him being a top flight relief pitcher for so long. Besides, the winning team is obviously too excited to do any sort of walking. So please, if you use this term, please use it properly. And if you hear an announcer misuse it, throw something at the screen and tweet them a link to this post.