EU has much more strict policies, limits on pesticide use, no GMO rule, plus specific laws to protect traditional (sometimes centuries old) product recipies from being faked by inustrial-scale producers, replacing natural ingredients with chemicals.
That's why food generaly tastes much better in Europe.
Neither impact flavor.
> replacing natural ingredients with chemicals
You do realize that "natural ingredients" are chemicals too right? Everything is made up of chemicals.
How is natural vanillin any better than synthetic vanillin? Matter is matter. Organic molecules are identical whether a plant produced them or a chemist.
Vanilin itself is a good example of the exact same molecules, but for instance I remember on chemistry class discussing banana flavor extract: it tastes "like banana" but it's not actually the same chemical component. Making a cake with that chemical and labeling it banana bread could be done and probably won't taste the same.
But that's not where most bakers get their flour, most will get it from someone who specializes in delivering baking goods who will have a larger selection.
I think those specialized deliverers are more rare in the U.S., and so the baker either has to pay for more expensive raw ingredients, or use lower quality.
Go to any supermarket in France and buy flour for instance: you'll find type T45, T55, T65, T80, T110, T150 [1]. And professional pastry recipes will tell you exactly what type of flour in what quantities. In the U.S. you will only find "All Purpose flour". I know French pasty chef in the U.S. who struggles to find the right ingredients. Since people care about getting T45 or T65, the producers create them at scale accordingly, and so it's possible to find a specific flour for the same price of "All purpose flour" in the U.S.
[1] http://www.wessexmill.co.uk/acatalog/Flour-Types-T55-T45-Typ...