First, the word you need is “supposed”, not “suppose”.
Everything you say is wrong, you are mistaken. You seem to be actually asking about vegetarians, not vegans.
Vegans/vegetarians usually don't hate meat they have just decided not to eat it. It's like a fat person who goes on a diet doesn't hate fattening food, they just don't want to eat it. A person who gives up smoking doesn't hate smoking, they just don't want to do it anymore.
When someone gives up something they like, they'll often try to find a substitute for it - fake meat, alcohol free beer and wine, artificial sweeteners, nicotine patches, vaping.
COME ON wake up!
@ Katie, I'm sure your mum is a lovely person but she's certainly “unusual”- the majority of people who give up smoking do NOT do so because they hate smoking.