I've heard Susan Lucci has had people who believe she's Erica Kane slap her in the grocery store. Evidently she tried to take it as a compliment.
Now that's what I call professionalism.
Soap opera actors get it the worst. Even if the actor's been on different soaps or the character's been played by multiple actors.
Now, people who ask George Clooney or Noah Wylie for medical advice take the cake.