What ingredient adds the sweetness on Croissants in Europe? I'm travelling in Europe right now, and in France, Spain, and Italy I've had croissants and similar pastries. Unlike the ones I've had in America, these have a bit of sweetness to them - my intuition is that something like honey or agave nectar has been drizzled on top, either before or after baking. Does anyone know for sure? I'd love to try baking pastries more often when I get back home.
Sometimes, in the less refined areas, you'll get pastries with sugar syrup brushed on top with the egg. It gives a shine to the pastry that lasts for a long time, protects it from losing moisture and makes it sweeter.

This is why all the industrial pastries are usually so sweet.

I don't think that any traditional European patisseries have ever used Agave for anything, and I hesitate to think what their reaction would be if you suggested it.