That's exactly how it would be used. Game programming involves a pretty enormous amount of geometry and vector arithmetic, so it's a domain where being able to

That's exactly how it would be used. Game programming involves a pretty enormous amount of geometry and vector arithmetic, so it's a domain where being able to write s*(u+v) is an advantage over scaleVec(s, addVec(u, v)). Same logic applies to matrices, as you described. Personally, I think there are more important advantages of C++ over C, and operator overloading can get ugly FAST if you're not careful.