I did just literally say that this has never ever happened to me. Likely that's a regional thing, perhaps panel interviews are popular in USA - but my practice has always been 1-3 rounds of <1 hour interviews, at various sized places including a multinational bank (where I also did many interviews from the hiring side both for technical and nontechnical roles, but it always was ~3 rounds of <1hour interviews with no take-home tasks; if more people were needed, they were included at one of the interview rounds, not as extra time), a major government institution, and a matured tech ex-startup - and while your question was reasonable, IMHO framing your prejudicial assumptions as "how tiny are these places" was an unprovoked insult that's not entirely appropriate.