Most bikes sold in the US are sold for recreational use. People don't want to pay for something they don't need (fenders, lights, racks) because they simply can't imagine riding in the rain or biking to work instead of driving.

Bikes used for urban transportation are far more common in Europe, where commuting distances tend to be much shorter, parking tends to be even more non-existent, and fuel prices are much higher.

However, let's not over-generalize when we talk about "bikes."

In Europe, mountain bikes, road bikes, etc. -- bikes sold for recreational/athletic use -- are no different than they are in the US. It's that in Europe the category of "all-rounder," a bike that's suitable for commuting, touring, audax, etc. -- is very well-developed, whereas that category is almost non-existent here.

However, it's still true that often the very same bike (look at Cannondale's US and European sites, for example) is sold fully equipped in Europe but not in the US. Different markets.

RichC