to reduce rubbish

when i was a child there was a deposit of 2p on every lemonade bottle
these were always returned to get 2p off the next purchase
boys would collect abandoned bottles to increase their pocket money

if the greek government introduced a deposit on plastic bottles of 10 lepta
( to begin with ) people would begin to return empty bottles
if after, say, 1 year, sufficient were not being returned to reduce rubbish
then the deposit could be increased to 20 lepta,
more people would return bottles = less rubbish
the deposit could be increased every year
until all/most plastic bottles were being returned

a 20mm red D could be added to all labels
with the date of production and the necessary deposit
( needed if deposits are to be increased in future )
bottles brought into greece by travellers would not have the red D
so would not have a refundable deposit on them

once it had been established that this system works
deposits could be put on all sorts of packaging that ended up as rubbish
cans, cigarette packs, glass, etc
this could be phased in adding a new package each year

this would cost the greek government very little, or even nothing, to introduce
bottles would be returned by consumers, children, tramps, etc

manufacturers and traders who sell these products make profit from sales
and are part to blame for all the rubbish in greece
they have some responsibility to collect the empties
and return them to the factories or waste collection centres
( after removing the red D from each package )