Not sure what's going on with the laws here (Greece), but if i exhcange my bitcoins to euros and transfer them to my bank account, i think if the amount of money is big then they will invenstigate where did this money came from.
Considering what's actually going on in Greece, i'm sure they'd investigate any significant amount of money moving between accounts be it related to bitcoin or not.
Would it be possible to cash-out via those Polish Cards linked to bank accounts? Should be able to do this with smaller amounts.