If you can be diplomatic about it, tell him that spreading that much bait is unhealthy for the deer and aids in spreading disease. The deer all eat from the same pile and share diseases. Just like people all touching the same surface and all getting the same cold.

Because of TB and other diseases, in Michigan, you can only put out 2 gallons of bait in a minimum 10' x 10' area.

In the end though, since there is no regulation in Ohio for how much bait you can use, you may just have to move on. As others have said, it is his property.