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.