I use people I know in stories all the time. If I knew you in junior high or high school, there are good odds you've appeared in one of my novels. There are even better odds, depending on whether or not you were a bully, that you've died a messy death or three in those novels. But I defy anyone to point to one of my characters and prove they can identify themselves.
If you weren't a bully, I might have borrowed a single thing from you to put in a novel. Occasionally, I see someone who has a look or a feature that I find intriguing. I'll assign that to NPCs in a book (Non Player Character, for you non-gamer types). The NPCs in my books are characters who walk on, do one thing, and then walk back out. Nothing bad happens to them. In fact, they get no story of their own. They're color. Set dressing. Customers in a shop. Soldiers guarding doors. It is possible that someone could identify these characters in a "Hey! She totally stole that pink hair thing from me!" kind of way. That said, I seriously doubt that the people I am lifting wardrobe or dye jobs from actually read the sorts of things I write. Also? I keep it as general as possible - like pink hair. No one individual owns that hair color. So if I see it on someone and use it for an NPC in a story, it's pretty tough to say I took it from that guy over there in the skinny jeans with holes in the knees. (All of which I just made up. I'm sitting on the boat, staring at the unbelievable mess that's been made this week.)
Main characters are almost always products of imagination. I say 'almost' because there have been cases where I kept a personality type in mind when writing, but that's as far as that goes. The protagonists and antagonists need to be specific people in order to serve the story. Even if I'd wanted to model an MC on a real person, in order for the story to work, I'd likely have to change so many things that the real person would be lost. So I just don't.
What about you? Do you think it would be cool to be written into a book? Would you want to be a major player in the story? Cause you know some terrible things have to happen, then. What about being a bit player?