Why haven’t flat-Earthers trraveled to the edge of the Earth and taken pictures to prove their position?

They have.  First they stand on the beach looking at the flat horizon past the ocean.  Then they fly on a plane to a destination beyond that horizon and look back at where they came from.  Same flat horizon, still there.

Will a picture of Antarctica prove to you that the earth is flat?

Carl Sagan  -  "You can't convince a believer of anything; for their belief is not based on evidence, it's based on a deep-seated need to believe."

Ferdinand Magellan  -  "The church says the earth is flat, but I know that it is round, for I have seen the shadow on the moon, and I have more faith in a shadow than in the church"-

Right? They could fly past the edge. 

Same reason liberals cant show any proof of socialism working.

I've seen interviews with these people and most don't really believe the earth is flat. They just like the crowd.

Too dangerous. They would be swept over the edge and fall off.