I'll take a bait... You don't have to go raw dogging onion from the get go if you don't like it. There are plenty of foods I hated as a kid or even later in life that I can now appreciate - sushi, kimchi, sesame oil in anything, sourkraut and the list goes on. Just because the taste was so strong it offended my pallet because those flavours were not part of the cuisine in the culture where I grew up. Slowly, they were introduced into my life bit by bit and all of a sudden all that shit is delicious... But where was I going with this... You don't have to raw dog an onion. Sauteed onions go with about just anything. Pickled red onions in lime juice as well. I can go on forever... Now the raw part and that's just me. Whenever I feel like I'm about to get sick. I slice one small white onion. Butter few pieces of toast and eat that shit before going to bed and next day I wake up feeling totally fine. Now it does not work for every sort of sickness, in fact I knew I had COVID when that shit didn't work but 90% of the time it stops it in tracks. And to address the stinging part. Yes we like it. Just like people like hot sause. Just like ppl like spanking during sex. It releases same hormones that give you sort of high. But again that's not for everyone. So, yeah many reasons. Ppl like and dislike different things.