I think it was mainly Google. In the 90's companies didn't have time for all the drama; for instance in 1998 I went to four interviews in one day. These were

I think it was mainly Google. In the 90's companies didn't have time for all the drama; for instance in 1998 I went to four interviews in one day. These were typically 1-2 sessions with the hiring manager and a tech lead. The content wasn't that different, but the format was simply shorter, and things like education and references were used. The economics of this practice are interesting; I believe it's Google's brand of conspicuous consumption (and aspirations to it) combined with Confucian bureaucracy.