...and that brings up another question. Just how far apart were Sunnydale and LA? At Joyce's funeral, Angel seemed to be there almost as soon as the sun went down. Granted, he could've gotten there during the daylight hours by either having someone else drive an enclosed vehicle, or he could've gotten there so near to dawn the previous day that traveling to Buffy's house would have been impracticle if not downright impossible, but in that case, wouldn't he have called to say he was coming? Also, he obviously left before dawn, because he wasn't there the next day, and, if "I'll be here for as long as you need me," means anything, Buffy surely didn't need him for very long (of course, her show was on on Tuesdays and his was on on Wednesdays, so he had to get back in time for his next episode).
I guess I'm trying to read too much into a simple scene, but, as I said once before, those sardine and peanut butter sandwiches late at night...