As a ginger (ah the shame of admitting it
) I've never quite understood why insulting someone's hair colour (something genetic/can't be helped) is really cool and funny and top quality banter m8 that is broadcast live to the nation on prime time tv all the time, yet insulting someone's skin colour (something genetic/can't be helped) is horrific and should never be done ever. Surely promoting any form of discrimination should be looked down upon in an equal manner? Yes, it's a great laugh hurting one persons feelings but hurting another persons feelings for essentially the same reason is terrible.
However in this particular situation it seems that Katie insults anyone and everyone for whatever reason pops into her head first so I don't think anyone should really take offence.
she almost certainly doesn't believe anything she says, it's all just an act for this character she's created of herself.