Answer on economic question.

Why do the keypad buttons of drive-up cash machines have Braille dots?

The answer on that question is so easy and simple to our surprised. The buttons have Braille dots because of the money savings, to make our life easier, so dots are on the keypad, because it would be very hard to made two manufactures, which will provide production of two kinds of buttons. The solution: they make one manufacture, which makes only one sort of buttons, which cause that the average price of one button is cheaper.