I know its not a great return but have you looked at the
xbox reward program (your based in germany right? im sure they are part of it) Dependant on your gamerscore you get a rebate on all purchases over £10, i believe it goes from 1,2,3,4% based on your gamerscore. Which yes before would of been tiny amounts but if you are buying a full retail game for £50 it could be a few pounds back each times which will add up if you get a few a month. Atop of that for each new release you play i believe 5 or 10 hours of a month within its launch you get money too along with other things.