I dislike the increasing use of interactive voice response (IVR) systems that require you to talk rather than use the keypad. Part of it is that I feel weird talking to nobody. I understand that is a personal opinion, and that some people feel more comfortable speaking words rather than using a numeric keypad.
The more important concern I have is that it makes the call less private. I'm sure the service providers are good about making sure highly sensitive information like passwords or social security numbers are entered through the key pad, but I still say somewhat sensitive information when I work through the menu of a health insurance or a financial services company. I don't necessarily want people in earshot to know that I'm calling to check on my claim or checking my bank balance.
A corollary is that others nearby might not want to hear my business regardless of its content, so being able to conduct as much of the call in silence is the considerate thing to do.
One can respond by saying I shouldn't be making such calls where I'm concerned about privacy or disturbing others, but that's not very helpful. The whole idea is that these systems provide valuable and convenient services, so suggesting I work around an inconvenience is missing the whole point.