It didn't make any sense for Obama not to actively campaign in WV - however, if your opponent is $20 million in debt, can't paid her vendors, and needs to recoup the $11+ million dollars that she "lent" her campaign then maybe you throw her a bone. The more magnamious the gesture, the bigger she wins and contributors - especially the little boy who sells his bike and video game - start filling up the electronic campagin kitty.
In return, she stops going all negative and begin to prepare an exit strategy.