I am very jealous - being relatively young in my career, I don't see much vacation. Prior to my current role as a manufacturing engineer, I was in consulting, which afforded 5 weeks of vacation. Also, if you were not on a project, you had "free" paid vacation, which happened two years ago, giving me 10 weeks off during hunting season - a dream come true.
I save nearly all of my vacation for hunting season. I also get out before work a few times a week. I did not track days in the field this past year, but I would guess between 30 and 40 days.
Guess that's a great reason to look forward to retirement!