I understand that in other countries, this is seen as having a "hang up" about natural body parts.
I am not very modest, but I really don't want my nipples showing in any professional situation, just as I don't want my azz crack showing, or any cleavage. In my job, I have to be aware of what might be "triggering," but I would be like this in any work situation. And I don't want others to see my underwear, either.
This may be cultural, and that's OK. Jobob, you didn't need to delete your post; I think everyone understands that opinions on this issue differ in different places.