I am a bit baffled at not believing in split ends - you can see them, peel the splits. Some of my split ends have split ends themselves!
I don't go to hair dressers because I can't be arsed, but split ends are still real regardless of the existance of hairdressers and their need to sell their services.
My dad...
Does not believe in hot water bottles when its cold (or electric blankets, apparently you'll piss the bed and electrocute yourself. I am 43. I have not pissed the bed in quite some time)...
Fans - in summer, when its hot. This is probably linked to him living in a very cool well insulated property that in summer can still be cold enough to warrant lighting the fire... but yeah, fans aren't a thing, no one needs them, ridiculous.
Drink drive alcohol limits - apparently HE can drink 3/4 pints of bitter and he's fine - because he was ONCE pulled over after that much and was just about ok (he had also JUST eaten a large meal and only just finished the last pint, half an hour later and I suspect he'd have been way over). We have resolved this issue by taking him to the pub rather than letting him drive, which is a pain as he HAS to go every night.
My mum...
Did not believe people on the internet were real. This really confused her when I messaged her (having set her up a computer and internet, once she'd grasped it was like a HUGE encyclopedia and could be used that way), on MSN messenger. She rang me to tell me I was talking to her. I said I know, I am talking to you on messenger. 'But how can you be, people online aren't REAL... not REALLY real....'
Hid all her sherry and vodka because I'd steal it. I did not live with her and at this point had been tee-total for fear of becoming an alcoholic like her, for 8 years! Even when I drank, i didn't touch sherry or vodka. But no she HAD to hide it or i'd nick it...
No one can eat more than a McDonalds Hamburger (no fries, and just a cup of coffee or tea). All the other available meals are gross, ridiculous and in fact no one can eat them (not that no one SHOULD eat them. That it is impossible for anyone to do so!)
Both of them - in the 80s/90s...
Baths once a week, wash your face/hands/armpits/crotch daily at the sink. Anything more is excessive, lavish and outrageously wasteful in terms of money and water.
Clothes - my school shirts (I had two) would be washed at the weekend. I could not have more. I also had only one bra. That combined with the washing thing... explained a lot about my teenage struggles!
Deodorant - is just perfume and pointless. I tried to explain they were both confusing body spray with actual deodorant but nope, not having it. I was a stinky little widdlindiddlin.
Short hair is a must - because having long hair is horrid and you have wet rats tails down your back and freeze as it dries and its a massive faff. Basically all the reasons SHE'D hated having long hair, so I was not permitted long hair. I spent YEARS having to prove (yes, pants down prove) i was a girl, pretty much until I got boobs at 10!
(My hair is now so long i can sit on it, it is a pain in the arse, i don't give a fuck!)
There is no difference between washing powder for the washing machine and dish detergent for the dishwasher (Dad) - as a result neither clothing nor dishes were ever properly clean. Also putting salt in the dishwasher (necessary where we lived) was ridiculous.
Conditioner is not necessary (so my short curly hair was basically a frizzball, and when i finally got big enough she couldn't pin me down to cut it - because hairdressers are not for children - a big frizzy mass!).
Pretty clothes - no idea why but as a kid, getting to pick through clothes in the hand me down bags we'd get from family friends, she HATED it if I ever chose a pretty girly item. I'd get to have it... if it fit, because it was free, but then she would object any time i actually wanted to WEAR it (and i did becuase it helped avoid getting de-bagged in primary school to see if i was a girl!).