I don't get what's up with the runtime hysteria. All languages have a runtime maybe except for assembler. And linux kernel itself is infamous for being not C by a large margin. And in general remove something important from any program and it will stop working.

If you do embedded work, you often want to be in total control of all memory allocations. So it is good to know that the compiler will not produce some invisible heap allocations and there is a useful subset of the standard libray that does not use them either.