I believe the idea is that there is an advantage in playing in your *real* home stadium so if one team played you there but another team played in a madey uppy home stadium the latter has an advantage over the former.
But I expect you realised this and still hold the same view that it is b*llocks. And I concur. Load of nonsense, we have more important things to worry about. Like where to eat in Lyon in a few weeks time, as an example.