"Now I'm offended. Here I thought it was all me," Buffy replied before he opened the door and headed into the building. So he didn't drink from people directly. That was weird. She expected most vampires to take their sustenance straight from the vein, considering the amount of helpless and, in most cases, willing slaves running about. Not that she was complaining, of course. A vampire tasting Slayer blood? Not so much in the realm of good for her cover story.
She was tempted to look around a bit, but she didn't feel much like pressing her luck with Ambrose today. And it wasn't even slightly because she felt kind of bad, she tried to convince herself. So, for once, Buffy did as she was told and waited.