If you don't want them on your own questions, just turn off the option to be anonymous when posting a comment on your question.
I do anonymous because when debating or whatever I tend to get pushed aside because of my age, or if I actually prove them wrong (which has happened) I just need to stop disrespecting people when they were the ones swearing every other word at me lol.
Anonymous users do have a username and profile. You just cannot see it in those instances. Some users only go anonymous for highly private information. Others choose to do it often because they prefer to keep their identity hidden, are extra careful with their information, and/or do not want to make friendships on the site by revealing their name. Yes, there are those users that like to be anonymous to troll as well.
No, even anonymous people have a profile, it's just that you cannot access their profile as a regular user. However admins will have access to their profiles and can see their name too.
I think they just go anonymous if they want to ask a question, or their profile may have very private info or something. It can be anything.
Just means I'm a ghost ;)
But I do have a profile; I'm only anon because I'm very introverted and this website offers anon opinions... and I tend to not troll, but if I do then I sure as heck try to make it very visible that I'm joking