There seems to be a continuing misunderstanding here. The 'oblige' in 'noblesse oblige' is an obligation upon the nobleman to behave well to his inferiors; it is the very opposite of what you implied in your original post.
As for Wikipedia, well, I will muster all the scorn I can. A worthless trifle, by the ignorant, for the ignorant. Facts are not democratic. The meaning of words may be, but I'd even there I'd rather read a definition by someone who knows what he is talking about, and has the respect of his peers, than one by a fellow who has, in effect, wandered in off the street.