Multi-million dollar horses, and they can't afford to put up some high fences to keep the deer out?
Good question.
I myself couldn't do it. I would get no satisfaction in sniping off deer with a rifle. I am not tring to discourage you from doing it. If you can handle the task go for it. You just need to ask your self is a new hunting spot worth it. Only you can answer that.
As has been stated those deer will wise up fast to being hunted and will be alot harder to come by come this fall. Maybe you won't even have to shoot to many with the added human pressure. What ever you choose, good luck.