Luxembourg saves on the barriers/checkpoints/controls that people actually paid for their tickets.

That said, it's a very small country and so the infrastructure cost are very contained. Also it's balance/budget is probably in the positive as well.

yes it is more like a city. it will be interesting for other cities to see if this works on this scale

As I recall Estonia has free public transportation for its residents. They started with the capital several years ago and expanded to whole country. I guess it worked out well for them.

It's more like a village.

> One pays for transport in both time and money.

Have you visited any big european cities ? I live in berlin and to reach anything in a 5km radius (and I very rarely need to go further than 2) the fastest way to travel is bicycle, the next is public transportation, the last is car. Ranking these by cost gives you the same order.

But you could say the same for building roads, if you’re comparing to cars.

Unless you’re implying they reduced the number of buses/trains to compensate, this is surely a very positive thing for the citizen.