Of course Sam would get there first. Dean was still trying to get back on the bike, slowly but surely. Instances like this where people were magically coming back from the dead didn't really help matters. First Sam and that whole deal, now this?
He was to the point where he was almost convinced that it wouldn't really be her - that it was some grand scheme to screw with his head, courtesy of some demon or shifter that had it out for them.
So entering the restaurant and getting to see her, and Sam throwing the holy water, made things more real. Dean gave a half smile to one of the waitresses before beelining to Sam and a scowl fixed on his face. "Was that necessary," he grumbled out. "'Cause last time I checked, there's better ways to do that."