This isn't inconsistent. Promos reprint of cards that came out at the same time were also SM promos (like the ultra beat GX boxes or tins)
I wasn't aware that was the case with those, but it's still weird anyway, there's really no reason why they SHOULDN'T be alternate arts. At the very least, it'd give Pokemon some flexibility if they decided they really needed to rotate a certain promo just past the usual cut-off or something.