There is going to be the "oops" deer every once in a great while. But ... nearly 20%?!?! That right there tells you that the hunters don't care about the plan or what animal it is that they are shooting. "As long as it is legal ... SHOOT!"
Just because something is legal, does not mean it is right.
Personally, I've not killed a button or drop antler deer in probably 20+ years. I'm pretty firm on when in doubt, don't shoot. I've killed some small yearling does in recent years and in every case I was 99.9% sure that I was shooting a doe and not a button.
I refuse to participate in the states special doe slaughter season.