Mark Twain quotes
Laws are sand, customs are rock. Laws can be evaded and punishment escaped, but an openly transgressed custom brings sure punishment. The penalty may be unfair, unrighteous, illogical, and a cruelty; no matter, it will be inflicted, just the same. Certainly, then, there can be but one wise thing for a visiting stranger to do--find out what the country's customs are, and refrain from offending against them.
"The Gorky Incident"