GCC, for example, allows a "-fomit-frame-pointer" [1] optimization option which would get rid of this. I'm not sure why this isn't done by default in optimized builds. Maybe it has something to do with stack unwinding: if the functions panics for some reason, or triggers a CPU fault, there's no way to get the correct backtrace if you don't have the frame pointers on the stack.

[1]: https://gcc.gnu.org/onlinedocs/gcc-3.4.4/gcc/Optimize-Option...