Yes, we do. It's called Freedom. And as long as it does no serious harm, we should tolerate it. Certainly not try to lose someone his job over a cheeky remark
Coo, exaltedwombat, so I can start making racist remarks then? Because they surely don't cause any serious harm, right? That's good to know.
FYI, it wasn't a 'cheeky remark'. If he had said, 'she's really ginger' or 'carrot-top' or something, that would be a cheeky remark. He said that the OP would have to get the hair-dye out to get rid of the hair colour. 60 years ago, I bet some people would have had no qualms saying to the parents of a mixed-race child that they would have to get the bleach out. But we realise now that this is completely unacceptable.
Bullying against red hair is a very real problem. Most people I know with that hair colour have faced extensive bullying during their school years and even in adulthood, have been subjected to rude comments and remarks. Katie Hopkins said that ginger children are less lovable. I have heard friends of mine saying stuff like 'I would be gutted if I had a ginger kid'. I have also heard people say that gingers should be drowned at birth.
NO other hair colour is subjected to this level of hate. It absolutely IS on a par with racism and the OP should absolutely certainly make a complaint against the 'cheeky' postman. Of course you can comment on other people's kids but you CANNOT say openly to the parents that the child's appearance should be changed. In 3 years time, the OP's DD might already be hearing this kind of crap at school and hearing the postman say it too would be incredibly damaging.