Seriously. I can't remember and I have no idea how all the ghouls got to Tokyo. Maybe this goes a little beyond the show but even if you google what a ghoul is, it doesn't say how it happens. Vampires bite you and it can turn you or kill you. Is that how it works with ghouls too?
Becoming a ghoul really wouldn't be so bad, the best way around it would be to eat humans that do wrong. Eating real criminals might not taste great (I'm sure it would taste the same as any other human) but at least it's one way of eliminating the things that are wrong in the world while curing hunger pains. I really wouldn't mind it, even if I was hated for it. I wouldn't be sure of what type of kagune I'll have as a part of me, I'm sure it woud be one that suits me best. Is it so bad to be something other than your own true self? I'd like to think I would be happier perhaps or at least useful to people if I were to reveal myself as a ghoul. I wouldn't know unless I were to become one. You never know, one day.
Because having power is fun ya it is because you wold be able to kill them having an organization wanting to kill you.. not so fun