The phrase "bait bag" refers to a bag that contains bait, which is used to attract animals or fish for various purposes, such as hunting or fishing. Full definition
The one we like and use the most are the Snap Open Bait Bag. (leerburg.com)
To each class you should bring: Lots of tiny chewy treats the size of a pea, some type of bait bag to easily access your treats, a flat collar and a 4 - 6 foot leash on your dog (NO retractable leashes in class please!). (puppyplease.com)
In continuing support for our veterans and wounded soldiers, LRR sent 50 training treat bait bags and 50 bags of Zukes treats to the Washington Humane Society for their «Dog Tags» program, helping wounded soldiers from Walter Reed Army Medical Center learn animal training, care, and welfare. (lrr.org)