Indeed. But that's because the whole Ultimate Question thing in Hitch-Hiker cleverly combined being funny by being true with being funny by being absurd; there's a real point in there, and there's also wild exaggeration for comic effect, and the point you mention is part of the latter.

ETA: not to mention that it's also cracking an unrelated joke about computers, and their tendency to occasionally do completely mad-looking things which it can take a lot of thought to realise were exactly what you turned out to have inadvertently asked for.