[AM407]

Could also be a difference in cone seat vs. ball seat, but that wouldn’t explain why they specify open-ended. Probably the mounting face of the steel wheel is thinner, so the lugs end up being too long.

And yes, open ended means what you think. They only seat on one side though, so you can’t properly put them on both ways.

I guess just order the proper nuts from the dealer? It’s a bit of a PITA having two sets though. I’ve done that for the past 12 years on my VW (OE alloys for summer and aftermarket alloys for winter) and am hoping to avoid it on the Crosstrek. But if the seat is the same for both wheels, you could just use the open-ended ones for both sets.