You probably already know this, but setting up a cross-compiler toolchain is a super annoying task, and is very dependent on the distro you're using. I'm sure the author knows about cross-compiling, but he probably preferred clear instructions that work for any RPi user.
There might be even stronger reasons to not use cross-compilers such as weird bugs or compiler version compatibility issues.
There might be even stronger reasons to not use cross-compilers such as weird bugs or compiler version compatibility issues.