Just the other day, I sighted two such bikes in my evening commute alone. Neither one is a brand I've ever heard of being distributed in the US, so they're almost certainly self-imports. I would suspect that they're typical run of the mill city bikes, nothing fancy or exotic- the classic bicycle as appliance.
The first one, which I see quite often actually, is a modern version of the type:
|Note the cable activate front drum brake|
Searching the internets for information on the bike- I see that I've already photographed this bike in Cambridge at least once :) It has a very distinctive coat-guard. It also has a slightly fancier saddle (leather brooks) than most European city bikes do, which mostly make do with rubbery waterproof vinyl saddles.
The second bike is a little more typical of the everyday bikes that are used in the hundreds of thousands in many European cities:
I like the head badge image of a pointer dog quite a bit.
I started my relationship with city bikes when I lived in Italy, and I self-imported the generic no-name city bike that I rode there to the US, and rode it for many years until it became too difficult to get replacement parts and the rust started to eat it alive. Somehow I suspect that this flow of bicycles is one way, and that very few Americans who go to live in Europe bring generic Treks or Huffys to Europe with them.