I'm not out to piddle in anyones pond, but I prefer to shoot in Mother nature. No additional costs, and availability is second to none - it's there when I'm ready.
I suppose. But, I'm increasingly wondering about the real differences.
Yes, for me, I really enjoy seeing a red tail hawk circling overhead or a great blue heron fishing in the local lake, and I enjoy the challenge of capturing these animals on film. But, I also know that if I really want to get close up shots of herons or red tails, I'm better off traveling somewhere where there are a lot of them and they are more predictable.
It depends on why you're photographing, and what you intend for your photographs. If it's for your own pleasure and benefit then it's up to you. If it's for sale then my ethics would require full disclosure. There's a HUGE difference between an up-close photo of a tiger in a game park vs. an up-close photo of a tiger from the back of an elephant in India vs. an up-close photo of a tiger when you've stalked the critter on foot, and there's nothing between you but a telephoto lens and a can of bear spray.
When selling photos, the TRUE STORY of how the photo was made is essential to an ethical transaction. When photographing for yourself you're not fooling anyone, so go have fun.