Good points everybody. For many, the problem is having been raised in a belief system that totally ignores epistemology - the science of how we know stuff. In Watchtower land the answer to that question is "because the GB says so." In this system, it is perfectly acceptable to say "When Jesus said 'this generation' he evidently meant two overlapping generations" without showing any evidence whatsoever.
Some people never get over that sort of logic, nor do they learn how to determine the truth or falsehood of information presented by others. Some parts of the internet are wonderful, others are giving the WTBS a run for its money in the production of BS.