Of course some European cars have cup holders (I have no idea how many models on today's market have them, maybe lots of them do), it's just that perhaps cup holders are traditionally more common in American cars because of food-obsessed America
European car-companies have to create cup-holders (at least one for the driver and one for the fronnt passenger) in their products, if an export to America is planned. I don't know, which car it was, but some months ago one company has forget them - and the US-dependances were getting mad about this fault. So they had to repair their mistake.
But cupholds in European cars are mostly a joke. You should never use them! So the older Mercedes, W 124 and so, had just two round places in the inside of the glove-box.
And European cupholders, are CUPholders, not big enough for the large McDonalds-drinks or even 0.5-liter-bottles.
Why don't use them? Easy explanation: the European ones are mostly placed close to the stick-shift, inside the glove-box, or it's a push-out-holder in the middle of the dashboard - so if you make a harder brake, have to go in sharp curves or are on bad roads, your drink will be splashed into the dashboard, the glove-box, on the switches in the middle-console, over the radio and so on! Pure bullshit!
Even if I' driving a car with a cupholder (my K 70 doesn't have one, the Opel Omega only the rounds into the glove-box), I never use them (except last Februrary in our US rental car, the 2008 "Town and Country").
I usually have bottles with me, never cups or these wobbling McDonalds-drinks. I put my bottles on the passenger's seat and fix them with my jacket or a bag. If someone is with me in the car, I put them on the back seat, in a way, that I can reach them while driving.
In my K 70 I avoid that place, because it has light beige seats. There I put the bottles on the ground in front of the passenger's seat, fixed also with a jacket - but on the door's side, because i nthe middle it's geting warm by the exhaust underneath. Warm Diet Coke, lemonade or juice is worst!