It never occurred to me that immunizations might not confer immunity. The college made the whole staff have the Hep B series about 15 years ago and I'd be aggravated to learn that it didn't "take".
As far as M and M and R, my sibs and I had intense cases (well, chicken pox too) and were exposed time and again before the immunizations came out. Suurrely we're immune, my doctor father probably brought home everything!