If nothing else, didn't she still have the phone in her hand? Or maybe she was in a difficult spot to place a good throw. I mean she couldn't get the bottle to him, maybe he didn't think he could get it to her? Did the author say that he never did it again? Rather then this horrible kind of arm-chair sleuthing it's probably just easier to ask him why.
[1] funny enough, you suggesting this makes it more apparent that you think this way. I mean, this never occurred to me.