It is used by other businesses and offers a good option when the phone lines are flooded with calls. There are many posts on the boards about people being on hold for several hours, if they were lucky to get through at all.
The person doesn’t actually dial your number, it’s done by computer. When it’s your turn you pick up and then are connected to a representative. If anything, it cuts out the time one explains how they have been on hold for X hours.