Fellow European checking in, I can confirm that cup holders are disgraceful things that clutter up space because those overweight Americans just can't go for five minutes without ingesting water sweetened with corn syrup.

(we have an unobtrusive cup-holder between the backs of the front seats, I don't remember ever using it)

I don't think Europeans really think that about Americans, but I suspect a cup-holder, while convenient, might also give the car a bit of a subtle "low brow" feel that make people slightly less comfortable in spending large amounts of money on it. A bit like how a comfortable bike seat may be better and more comfortable by all metrics, but be shunned because comfortable seats are for pussies. And from a business perspective, if 1% of people complain about cup-holders (but buy anyway), and 10% of people subconsciously reduce the worth they give to a car because of cup-holders, then including cup-holders is a bad idea!