It is interesting indeed to come across people who are willing to believe in things without any firsthand evidence with which to support their claim.
That being said, this practice is by no means exclusive to flat-earthers, round-earthers, hollow-earthers, simulation-ers, solipsists, nihilists, conservatives, liberals, etc.
The tendency to ridicule and target a group whose beliefs challenge the current mainstream narrative, (evidence of which can be seen during the spanish inquisition, the salem witch trials, the commie-scare of the 20th century, etc.) threatens to further weaken any potential conversation and coexistence between groups with opposing views.
Can't we all just get along?