I discovered that mice have a taste for tobacco seed a few years ago. My bagged seed heads were hanging in the shed. The mice (which I never actually saw, but which left a clear trail of mouse poop) apparently climbed the shed wall to a shelf that was closest to one seed bag, and jumped to it. From there, they could climb onto adjacent bags. They munched right through the Agribon bags. The only seed I recovered from two of the bags was what they spilled into the bottom of the bag, and hadn't bothered to clean up. For the past several years, I have been bringing my bagged seed heads into my enclosed back porch for safety.
I used to put out poison for mice, but after noticing a number of dead birds in my yard, and an occasional moribund mouse struggling through the grass for its final journey, I decided to just go with mousetraps.
Bob