On my recent vacation to the Netherlands, I found the Dutch to mostly be very nice -- especially at shops, cafes and restaurants. Unfortunately, I had 2 encounters with locals in Amsterdam -- one young woman on her bicycle and one male on his scooter -- who behaved in a way which I would clearly describe as "rude" (i.e. the young woman yelling "idiot" to my face).
What I learned is that the Dutch have "road rage" on their bicycles and scooters the way Americans do when driving. Since it's often their primary means of transport to get from one place to the next as quickly as possible, they have zero tolerance for any obstacles in their way. Word to the wise is to not take their verbal "abuse" personally, as it's their cultural norm to be direct even though it comes across as rude to those unaccustomed to such bluntness.