Sam and Dean Winchester knew better than anyone the dangers of hunting. By the time Dean was fifteen, he was firing wendigos. By the time Sam was eleven, he was stitching up his brother and father and shooting werewolves.
Over time, the injuries increased in both severity and number. They both landed themselves in hospitals more times than they could count, and it took more than a concussion and some broken ribs to land them there. But they were young, and they were invincible, so they just kept going, side by side in an Impala driving down the open road.