You're appalled by the proper, scientific term for person of black heritage? Are you trying to change the vernacular?
I use negro quite a bit and have been known to use Mongoloid when referring to any person of Asian descent if I was unsure of their actual pedigree.
You can be appalled and offended all you want, but these terms are part of a proper lexicon. Just because a community takes offense to a term, doesn't mean the term itself is inflammatory. It means someone takes offense to it.
For centuries, whites used the term "nigger" to refer to blacks, and it was considered inflammatory by blacks during the 1950s and 1960s. NOW it's part of the black vocabulary in every day use, but some how it's not considered inflammatory anymore?
I'm part Italian, and I take offense to the term Guinea Pig. Does that mean that we should stop using the term Guinea Pig to refer to Cavia porcellus?
"Nigra" was acceptable - "good" negro or a negro who was your buddy even if you were white was a 'nigra'.
If you were 'useless' - not a workable farm worker you were the other "N" word.
Whites I knew differentiated between "nigra" and "n word".
The "n word" was used despairingly by whites AND blacks. I don't know what is acceptable terminology now as I left the farm many years ago.