[Karellen]

> There was a time when some old installers wouldn't parse "Program Files" correctly because of the space.

That's one of the reasons why it had a space. If you wanted to stop using the DOS APIs and get off of `PROGRA~1`, you need to handle spaces properly. Having a bunch of the standard paths (see also `My Documents`) include spaces meant that software vendors shouldn't have been able to get away with using Windows filename APIs without supporting filenames with spaces - everything would obviously break almost instantly.

Doing that, Microsoft made sure that there was no reasonable way for an ISV to claim that they either forgot to test that use-case, or weren't going to support it, when every Windows system in existence relied so heavily on paths with spaces.