Up to them.
Nothing wrong with that.
My new name is going to be Alexandro.
Well, actually not really.
Actually.....how do you know that they dont have historical and
heritage reasons to do that.
For example, there are some people with name like.....Da
Silva.....De Cruz......
They may be descendants of past Portuguese settlers.
(I am not clear about this)
It may be the same case with those people in Facebook that you
see.
You may be confused because they look non-Westerners, but maybe
because they are distant descendants (already mixed race), so they
are confusing.