I use Google Fi and I've been to the Netherlands, France, Spain, Italy, and Switzerland. When I landed, I'd get a text message saying something like "Welcome to $COUNTRY! Your data is $DATA_RATE per gigabyte and voice calls are $VOICE_RATE per minute. It may take a couple minutes to get connected"
DATA_RATE has always been the standard Google Fi rate of $10/GB (with data free after a certain point, and free but throttled at another threshold), and the voice rate is typically 10 cents/minute.
For people that do a lot of travel and use a lot of data, you can even get an unlimited international data plan.
But yeah, I can go to nearly any first world country, and even some 3rd world countries, and not pay extra for my data. The fact that Verizon/TMobile/Sprint/etc. can't get their shit together and make this happen for their customers feels like a scam.