Tons of people pass through and survive, but their stories are not televised, hence the reason not too many know.
The floor of the Gulf of Mexico is caked with hydrocarbons beneath the silt layer. This is a material that is solid methane mixed with the earth. The stuff stinks and will burn if ignited. Due to volcanic action down below, the heated hydrocarbons begin to bubble. When massive amounts are released, this can cause an entire vessel to sink due to loss in buoyancy. Same for any hapless aircraft flying above.
Discovery Channel ran a special on this a few years back. A couple of professors ran a test on a model scale tank of water with a model ship. With the right amout of bubbles released, the vessel did sink. Also, Discovery Magazine had an article on hydrocarbons, better explaining their existance and impact on our society.