For years I went in a bottle and my buddy who's a biologist -- and bow hunter, used to tell me that's worse than letting er' rip. He said once oxygen hits it, deer can't tell it from anything else. However, as stated earlier, the bacteria and amonia build up is like a flag.
So about 8 years ago, I decided to try going whereever I was. I have not seen ANY negative impact that I can tell. However, I've even went on a down tree below me once and had two bucks and a doe feeding on it. And I always go in a scrape.
I guess it's ok.