Celebrities and anime voice actors- what are they like in person?

I haven't really met any voice actors or movie actors, but I have seen them in person and when to some of the forums at some cons. Most of the voice actors I have seen were the main ones from Full Metal Alchemist. They seemed very nice, and very funny. Though I can tell you my mom has met William Schatner, who she rather idolized and loved back in the day. She has told me when she went to get an autograph from him, he told a rather mean joke in front of the other people in line and basically called her fat. After that my mother of course, no longer liked him since.