Silly question but is it dark when you get home? Just because on the Mk5 if the lights are on because you were driving a bit quick or because the wipers were on constantly then they switch off as soon as you take the key out, they only stay on for a bit if its actually dark. Sometimes if its twilight mine switch off as soon as you take they key out but other times when its proper dark they stay on for a bit...
Mk6 may of course be different...