Sometimes the phone company send me letters that i dont know what it is about an unknown discount and when i call a machine answer this dial 1 for this or 2 for that, put your phone number and a lot of stuff when just a regular secretary can answer just a simple question what is this letter about tell me please and thats it.
On most telephone prompters, hitting "0" is your escape route ... it often directs you to an actual agent. Try it out next time and see if it works with that specific company.
Because there are a lot of customers, way more than actual workers. It's more efficient for the company to have machines.