I have to disagree with you. The thing with tech support is that you are telling the end user how to do something diffrently then they have been doing. Sometimes that is somehing they have been doing a certain way for a number of years.
When someone calls an electrician 90% of the time that person hasnt even changed a fuse or a breaker in thier lifetime, but in tech support your telling someone how to do something with a computer that they have used for a really long time. Hence they believe they have expert knowledge of the system they are using.
They get away with it for a period of time until something happens that hinders thier way of operating thier system to the way they are used to. And telling them they have been doing something wrong the whole time and they need to change thier habit not only brings suprise but also resent.
Without being specific younger generation accountants and financual systems come to mind. They do something a certain way in a system for awhile that essentially will break the process of something that needs to be done quarterly or yearly.
Save yourself! Reboot in 5 seconds!