Before the FAA allows UAV airliners to begin service, they'll demand to see a great many hours of "proving flights" in airplanes which have both the robot system and safety pilots on board. Then the manufacturers will have to convince airline CEOs that the system will save money, and do so quickly, not just in the long run. (Today's revolving-door executives aren't interested in the long run.) Then the airlines will have to see if customers, regardless of what they might say now, will actually book flights on UAVs.
Until all of these things happen, such airliners are just a dream.