People wanna hunt pigs, and they wanna pay. Hunting provides extra income that many farmers need.
On the other hand, many farmers turn to so-called professional hog removal people and get burned. Live pigs can be sold on the hoof, so arrangements are made to tend and empty traps and share the take with the farmer. Then the traps suddenly dry up, home built or purchased, traps are expensiv ans often provided by the farmer.
Many farmers have issues with pigs leaving alive.
Many ranches are large enough to absorb the impact of pigs.
Pig hunters have a bad rep with farmers. Hogdoggers are particularly mistrusted. It is a false assumption that hogdoggers release pigs to to perpetuate thier activities for the future.
These are not my views, I know a lot of farmers and these are their opinions.