Sure, and we do. I've had agents tell me to use the kiosk, and I've resisted because I knew there would be an issue with the kiosk (e.g., a flight was cancelled and up until a few weeks ago an agent needed to intervene). No one has ever *forced* me to use a kiosk. But, it takes time to get people familiar with the technology, and some people will never use it unless encouraged to do so. My father is a good example of this. Guy has never used an ATM. We showed him the kiosk one day. He was hooked ... said he'll never wait in line again! Low and behold, he has lived by those words and doesn't wait in line anymore.
Besides, the MOST frustrating part of travel is waiting in line to check-in and watching agent after agent just typing and typing and typing and typing. The kiosks eliminate this frustration for many folks with the basic e-tickets.