That's an american way of seing things (and is only a thing in very few countries), because all your letters are on the num pad. But 555-فودكا is not going to w

That's an american way of seing things (and is only a thing in very few countries), because all your letters are on the num pad. But 555-فودكا is not going to work. And what next, do you accept exotic unicode numbers ? Letters that you casefold to something that can make to a number ? Again, you draw the line somewhere. There is no right place for the line, it depends of your business, but there is always a line of what you accept as a user input. Being offended won't help you on HN, and calling out people names either.