Inclusive and neutral language

My earlier post about racial slurs got me thinking:

What constitutes inclusive and neutral language is always changing, as we make a conscious and deliberate effort to eliminate inadvertent negative connotations from our daily discourse. So sometimes people don't know that if they use a particular word in a particular context, it could be interpreted as offensive, exclusionary, or otherwise give the impression that their intent is not benign.

What I don't understand is people who, upon learning that a certain word is not or is no longer appropriate and being told an acceptable alternative, stubbornly insist upon their right to continue using it. I'm not talking about using it in contexts where they intend to give offence or other contexts where they wish to include or allude to the negative connotations for a specific semantic reason - I'm talking about neutral contexts, where the strict denotation of the word is all that is intended to be communicated. But instead of using the word that they now know to be neutral, some people insist upon continuing to use the old word and insist that other people should simply not read into it the negative connotations that it bears.

Why, upon learning that a particular word could cause offence and that using it could give the impression that the speaker's intent is to cause offence, would a person beligerently insist upon continuing to use it? Do they know that this makes them look like assholes? Do they know that this gives the impression that they are deliberately and passive-aggressively attempting to cause offence? Why would a person who does not want to cause offence not immediately alter their linguistic choices to the words that are the most neutral and benign possible? What are they hoping to achieve?