I live in the U.K. and chip and pin cards are the norm here. Many common card terminals can only take chip and pin cards, although there may also be facilities in computerised cash registers which will handle magnetic cards.
The norm here is for customers to do everything themselves. You place your card in the card reader, and key in your pin when the machine tells you to. The shop assistant does not normally handle your card at all. The supermarket we use has self-scanners, and we also pay by card at a machine without needing to interact with a member of the shop staff at all.
Where there are ticket machines, parking meters, etc, a similar situation occurs. The customer inserts their card and keys in their pin. There is no member of staff available to help, and magnetic strips cards will not work at all.
In some shops and tourist locations, there may be many visitors from the U.S.A., and the staff will be aware of the need to handle cards differently. However, this is very much the exception. Most staff in shops, restaurants, etc will not be used to handling magnetic stripe cards.
I don't know what the situation is in other countries, but in the U.K. the card reading machines are not supplied by Visa or Mastercard but by the bank which actually handles card payments for the merchant.