In fact in many cases I wouldn't know if an artist is utilizing sample (as a technique) or not. They could have recorded them by themself as far as I know. I think the reason I don't like the way trance uses samples is because it is obvious it is a samples. For instance; they tend to use samples from famous movies and other well known sounds. It takes the edge of the music. It's like seeing the same actors/actresses in movies all over again. It's cheap.