How do some people find it hard to accept that some things are offensive to some people, even if not to themselves, and therefore to act accordingly?
You may find those people who are taking offense 'stupid' or 'over the top' or whatever, but it is no more up to you to decide they should not take offense than it is for them to tell you that you should. And surely the person or group who are offended, for whatever reason, have the right to be respected?
Thus we do not call black people 'coloured', we do not call mixed race people 'half caste'. Yes, these terms were fine when I was growing up, now they are not - I have managed to learn that. I am not offended by them for myself nor on behalf of anyone else, but I am grown up enough and capable enough to understand that if other people, individuals or groups, are offended or consider them inappropriate then I have enough respect for other people to just accept that without arguing.
Same goes for golliwogs, swastickers (Godwins law anyone?), mugs with 'I [heart] Chocolate' on them, wash bags with 'brown sugar' on them and so on.
There is no defending these things with "well I don't find it offensive and nor does my black friend", just accept that other people do and be kind to people.
As an individual I don't like being called 'love' by men. I especially don't like it at work. I am not 'offended' but I don't like it. So when one did, continually, I asked him not to. He got all defensive and said "what, what, is it like sexist then, it is non-PC....?". Why does it have to be those things? I said "no, I just don't like it so am asking you not to call me it. How would you like it if I called you PigFace?".
He stopped.
It's just general respect and kindness isn't it?