Driver's behaviour
The pedestrians in Netherlands have priority almost always. They are respected by the car's drivers and they have priority where there are not triffic lights. the opposite happens in athens..
The pedestrians must be very careful! Also the use of claxon in the streets is very rare(in Netherlands)but in greece very common. Greek drivers are very inpatient. (I think inpatienty is quite strong feature of the modern Greek...)

Food
A traditional Greek familly (even without the father or mother who is working normally till 16:00)should eat (a full) lunch around 14:00-15:00 and have a short siesta.
The dinner is also very important(around 21:00-22:00) and usually is a way of friends's gatherings in houses or out of the house for fun. So,going eating in the many different types of restaurants in the evenings, is the common way having fun even, daily. The eating schedule in Netherlands is very different and not so important as a social event.

Weight
Based of my observation I found that the majority of Greek men in the age range 35-55 have more weigth than the dutch men. Dutch women between 18-35 seems to me that they have more weight than the Greek women in the same age. Generally I think the tendency is the Greek men have more weight. The opposite happens in netherlands.

Super Market
The tendency in greece is to buy food and products for more long term. For example they are going once a week to the super market and buy a lot of products (even it's common during the week, to buy as well, some products from smallest stores). So, there is the mentality to have a ‘small’ super market in your own home. Dutch people ussally are going almost daily and buy products which cover one or two days.

Greek people because of a natural generosity they don't behave as a good customers. They almost never take back small coins (for ex.2-5 cents even 10 or 20 sometimes)when they buy products. Based on this the employers f.ex.in a supermarket,sometimes say “I'm sorry I don't have 1 or 2 cents to give back”, and the answer is: “It's ok”

Between friends (and sometimes not only) in a bar or in a restaurant it's very common one of them to pay for both, or even for the all company. So, somehow the 'hospitality' remains as well out of your own house. Dutch people are more strict in the way of payment and sharing. Almost always everyone pays his own.

Houses
The Dutch houses and the decoration are generally simpler without so fancy details, keeping a low 'profile'. Even they have expensive objects inside, the general line is more 'minimal' in Dutch houses. The Greek houses are quite luxurious even for families without a high saleries. They save money for a long term or the last 6 years borrowing from Banks, so that build or bay a nice house.

The attitude of possesion is very strong in Greece. The majority of the people have two houses in their own possesion. One in the city and one in the countryside. I didn't see this 'anxiety' in Dutch society.

Another difference is that Greek people are generally more open to invite and 'open' their houses for other people. Gatherings, dinner even meetings are very common in the houses. I think Dutch people are more 'closed' in this field.

The group thinking, talking and colaboration is very present in Dutch practice, fact is that it's not so strong in Greece.