Why does u8::swap_bytes exist?

u8::swap_bytes "reverses the byte order of the integer". A u8 value always consists of exactly one byte, so this method does nothing, by definition.

Why does it exist, then? It would make sense if swap_bytes were part of a trait that is implemented by all integer types, but it's just a standard method of the primitive type u8. Obviously, the same goes for the LE/BE conversion methods etc.