I've come to doubt that they really hold positive beliefs. Having had one IRL conversation with a supposed "flat earther", I quickly decided that they didn't really believe what they were saying other than to be "right". My response was to tell them that they didn't really believe it, and when they tried to convince me, I used the same "I know better" attitude on them.

Of course, they never convinced ME! Silly, wannabe flat earthers.