Can anyone tell me what these lights are for in the headliner and they can be turned off? 

At a guess, someone has fitted a W8 interior light and they can't be switched off 

Has VW Group not got some sort of "glamorous" name for these red LED down lighters, I seem to remember getting them when I replaced a leaking auto dimming rear mirror in my 2000 Passat - though you needed to place a hand below the rear view mirror to actually see them!  I think that my S4 has some somewhere, though again got too obvious - which was how VW Group intended it to be, I think that they are meant to flood you with a feeling of wellbeing??????? - without annoying you!

^^^^  submarine Lights  ^^^^

Like in Das Boot?  We went along to La Spezia when in Italy last year - didn't see any German Subs at all, they must have gone home!

They are not standard fitment if this is on the MK2 Fabia vRS you bought, so you will have to do something to cover them or remove them.