Rules like this usually exist because there were people who did the opposite at some time in the past. It's a simple enough requirement; isn't having it better than disallowing remote work, or disciplining someone for problems created by not having a door (kid runs in in the middle of a staff or client meeting) when no such requirement was previously specified?

I would say one of the tools required to be productive as a programmer is a focused work space. You can give that tool to people who come to the office. But if someone works from home, that's the one tool they have to provide themselves.