Before this app-madness, you would usually just check out with your debit card and pay for the time you used (common in Denmark anyway). No need to guess in advance how long you need to park for.
In most of the US you had to pay with coins. No cards allowed, and you'd definitely have to guess how long you'd take. Even in the few places that accepted cards you'd still have to pay for a time slot in advance, and go back to the meter in person to extend that time slot.