First of all, MANY aftermarket wheels are not hub centric because because to make every design of aftermarket wheel's center bore specific to every manufacturer would be ridiculously cost prohibitive OR the selection would be extremely limited.

"some are lug centric" - well actually ALL are lug centric ... or they wouldn't fit the car now would they !! In reality, they're NOT lug centric, that's just the bolt pattern, but modern manufacturing equipment and processes keep the tolerances tight enough that they could be considered "lug centric".