Unfortunately tipping is becoming more and more common in the Netherlands. Seems to be blowing (back?) over from the States. I wish places would just charge higher prices and pay decent wages and keep things simple.
In Denmark, I've had the waitress press "nej" to the tip on the card terminal once I brought out a Danish credit card. "Sorry, I didn't realise you were local."
A lot has to do with the blending of tourist-only places with more local places. In some countries, tourists typically tip, locals don't. But if you are a local and visit a touristy place, you'll see the tip expectation, and then this starts to permeate the culture.
It is? I haven't tipped in years, whereas I did in the 1990s. Maybe because I never pay with cash anymore. Then it was common to round up to the next multiple of 5. Even so, I never have had wait staff asking for a tip.