Well, yeah. But also:

> It is possible that foobar is a playful allusion to the World War II-era military slang FUBAR (Fucked Up Beyond All Recognition).

https://en.wikipedia.org/wiki/Foobar

Which is certainly how I've always understood it.

It seems the "foo" didn't come from that, but once "foo" was in wide adoption, the "bar" likely suggested itself automatically to someone familiar with "fubar".