It would be me basically saying the same thing that others have already so grandly said themselves.
Essentially, their facial structures are similar (objectively so), they're both ethnic (as someone said, if they got gotten a blond haired, fair-skinned boy instead it would be a problem), and it was aesthetically a good casting choice. The next best thing they could have done is actually generated a young clone of Morrison, and the only one asking that of Lucas is you.
Vaderisnothayden, I suggest looking up "cognitive dissonance" and reflecting on how it applies to this situation for you.