As far as my digging went, this is a feature, not a bug.
To resolve a URL, the code needs a document reference, and if the ```$xwiki.getURL``` doesn't get the document name (just the space with a trailing ```.```), it assumes it to be ```WebHome```.

Playing around with setting new values, to me it appears that there is no pretty solution.
The best that can be done is detecting if ```getURL``` got passed an argument with a trailing ```.```, and then after the URL has been resolved, strip it of ```WebHome```.
But that is too ugly in my opinion.

Is it possible to hide the ```WebHome``` in the URL bar without nginx?