Government envisions using revenue to ease transit congestion, support tourist sites
Archived version: https://archive.is/20251112161707/https://asia.nikkei.com/business/travel-leisure/japan-eyes-tripling-departure-tax-to-grapple-with-overtourism
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They probably have to give a reason that doesn’t outwardly say “we just want to profit more from this.” Japanese culture seems to value politeness.