ESPOO, Finland—Jannica Hartikainen recently had to have a pretty difficult chat with her 5-year-old daughter, Ciara, who somehow needed to understand that the powder-blue ice-cream truck that has long roamed the neighborhood to the tune of a happy jingle was going away.

"She almost shed tears," Ms. Hartikainen said, standing on the side of a road while waiting for the ice-cream truck with Ciara and her other child, a 3-year-old son, earlier this month. "She asked me 'Is this really going to be the last time?'...