Yes,... and since it never was supported by a big range of devices, it never was a very common container-format.
But I think Northbear is also correct, as I don't believe he is talking about the divx codec standard at all, but rather about the new-fangled and doodad-crazy video container format which is also called divx.
If I remember correctly, it is even possible to embed subtitles (.srt?) into AVIs as well, but only one or two at max. (and no, I do not mean the hardcoded stuff, where the movie-pictures are rendered/encoded with those).
This was developed by the commercial DivX group shortly after they finally accepted that they couldn't have a video monopoly using the DivX codec, thanks to the fully compatible freeware XviD codecs that homebrewers developed. So they decided to try for a monopoly on a new DivX container instead (abysmally stupid IMO), and as pseudo-motivation for this new container they added various features that standard AVI files don't have (multiple sound tracks and subtitles, and even interactive menus etc). And compared to a standard AVI file that is 'weird stuff' indeed.
Best regards: dlanor