There are a ton of us who are from one country, but moved to another, maybe more in EU than other places (not sure), but I really wouldn't say it's uncommon or even out of the ordinary. And I think most of us in this situation, have received/made international calls at least once in our life.
1. when travelling, hotels or car rentals may need to call or update me with some information
2. friend/family member was abroad and had issues with its own phone
3. some service I was paying for had customer care in a different country
4. buying something from a seller abroad, especially in the nicher categories (like a custom made standing desk) required the seller to call me a bunch of times