Crooking your little finger is well into Hyacinth Bucket territory. My MIL does it, along with a doily, serviette and cake fork obsession. She also uses settee, living room, sweet (instead of dessert or pudding), and copious quantities of pardon.
She is desperately insecure and needs to be seen as posh at every opportunity - of course like Hyacinth all her attempts just reveal she isn't.
I was brought up be sheer accident on What?, paper napkin, sitting room, loo, pudding, sofa etc - my mum was an au pair to some very smart people and that's how she learnt English. She then scrimped to send me to a prep school that taught the same words.
I've code switched since I was a child but as discussed above, I don't change all the words in a fake way - if I'm in someone's house and they say living room, I'll use living room and so on. But I don't think I'll ever say serviette 
I know the whole thing is silly, I'm judging anyone for what they say - except probably me for being so ridiculous about hating the word serviette! Oh and my MIL for trying to do class one upmanship on me and my mum because they have more money than us. You can't buy class, dahling 
