The idea is that they can't "get" to the dog food. Instead they have to roll the barrel around and the dog food falls out the holes and then they eat it.

So instead of one bear coming and gorging himself and then leaving an empty barrel they sit there for awhile slowly eating morsels of dog food.

If you can go in and bait every day or second day then that's great but what a pain!

This keeps them around the bait site for days and allows you to only go in 1 a week or so and replensih bait.