Have to agree it's a bit strange. Same story initially with the 500 as well though if you remember back. There standard A500 came with 160 bhp, ours only came with 135-140 bhp and you had to go Turismo/Competizione spec for the same power. Looks like the 124 spider will be the same, possibly have 2 choices of engine spec over here though maybe, although I doubt it. The 140 bhp here is to make the Abarth variant with 170 bhp look more performance based I think.
A jump of 30 bhp looks a lot better than a jump of 10...