Even with max happiness my guests will demand a refund 100% of the time when they exit the zoo, so I figured I’d make entry free so they could’t refund anything. And it worked! Though I obviously took a major dip in profits as everyone else, I can at least make money instead of going down in flames. Most of my income comes from donations, and it barely beats the expenses. So yeah, there’s a tip for all of you until Frontier fixes the refund bug. I hope.