What should the German middle class do?

They are getting stuck with the costs,  what is their demand?

Let Greece go, and put Germans on the Greek boards.  Start a small  micro finance intended to stimulate the reliability of the Euro as street cash.  Give the bond holders a share of Greek banks. Negotiate a European wide bankruptcy  of pensions.  The Germans should subsidize the micro finance for a while, sort of a loss leader. The Greek government can do what it wants as long as it is paid from taxes.

Fair deal.