Of course the GOP isn't treating him respectfully. I believe the point was that there's no reason for Obama to screw over Garland like that.
Exactly.
While I'm ambivalent on the confirmation (they really should at least put him through the wringer in confirmations and make their case why they think he doesn't deserve to be on the court), they're playing typical partisan games. They don't want their advantage on the court to go away, simple as that.
For Obama to essentially Charlie-Brown a respected jurist and yank away the nomination just as it's about to happen because he sees a better deal would be senseless and cruel. Unless Garland was in on it the whole time, but I seriously doubt that,