However, so long as they retain in Greece their high value added activities (their headquarters, their commercial and their research activities etc), this delocalisation in the long run helps both the host and the home country economy.
I always try to give an example: The UK lost some 3.5 million industrial jobs (50% decrease) between 1978 and 2003 and gained over this period some 3 million jobs in the financial sector (100% increase); as the value added in the latter may be 4 times higher than in industry, the total gain for the economy has been enormous and is the main explanation of the success growth story of the UK in the last couple of decades.