I'm a nurse, so bodies don't bother me at all...but there's a level of modesty that I appreciate when a person is out in public view. Unless a person doesn't possess clothing, it's just not necessary to expose nakedness to someone who may be tempted by it or those who would rather their children not gaze upon a naked adult.
It's one thing to expect privacy in your home when you have no near neighbors and there's only one road into your home, so you can feel assured you can go past a window naked without exposing oneself to any other person...it's quite another thing to parade around naked for no apparent reason in full view of a public road in the broad light of day.
No matter how beautiful the woman, it's unnecessary and part of that worldly drama that I eschew...it's clearly meant to cause a stir among others and not a bit about her own pleasure in being naked in a garden. As was pointed out, bugs, abrasions, dirt, etc. is a likely result of gardening, all of which can cause pain and discomfort to a naked body, so why in the world do it? Drama, pure and simple.