I'm currently finishing my PhD in Biology here at UCSD. This was a big change from physics and I am not directly doing much physics related research. However, I think my physics training was very important. I learned how to be a clear, critical, scientific thinker which has served me well here. Having a physics background in no way hindered my applications to biology graduate schools. I think most schools considered it an advantage. The field of biology is becoming much more analytical and the perspective I have with a physics background is quite useful. Now that I am looking for a job, I think having a background in both physics and biology will help a lot.

Physics majors can certainly go on to do all kinds of strange things, even public policy and international affairs:

https://elliott.gwu.edu/pace

Physics training has been an invaluable aid throughout my career despite my grade in quantum mechanics. : >

I love teaching (but then, I learned from the best), and love my research - it's trying to do both all the time that I am finding taxing.