You have some questions, it seems on your threads that are leading you to answers found in books or broadening the circle of people you talk to.
People I work with don't really see jews as a race and the blacks aren't always talking about someone screwing us over.
I get your points, but some of the things you're referring to depend on who you're around.
I see ur thoughts though.
To straight up answer your question: It's the same reason why Americans for over 200 years thought Egyptians were white.
White people and the jews who are white (not including black jews or mixed jews) have become the face of jews due to White history and culture publicizing it and through propaganda and because there are white jews and if you go to Jerusalem they look pretty white/mixed white looking.
According to the bible their blood line should not lead them to being white but black jews/ethiopians who still exist today as Jews migrated north and kept their religion and miscegenated. Thousands of years past and a very large number of white jews existed, then came Russia complaining about the jews and Germany going to war with their jews and colonization spreading the teaching that jews are white and the crusades enforcing the teaching among the world that jews are white and the Whitewashing of all history deemed important having to be seen as WHITE.
Getting back to your question; it's not entirely dumb for someone to see jews as a race (as it might be dumb for someone to call Latino's a race) of white people since if you go to the line of Abraham you were dealing with a specific family all the way from BC days; which this is who the jews are. Truth is according to the bible their bloodline is black.
Now aside from the points you're making, I don't know if this is necessary or not, but there are only four races: black,red,yellow,white
Jews are not a race. I don't think you were implying that though