Looks minor on your part, but bumper will likely have to be replaced. Depending on the speed of impact, other things might be damaged too (BMW bumpers are supposed to absorb impacts up to 9mph). Get a good body shop to check it out.

I think the safety aspect has to do with how people drive in respective countries. In european countries esp. Germany, the vehicles are driven pretty quickly on the highways and therefore have stricter European standards to meet. In Japan, I don't recall there being a highway stretch that has a limit higher than 100 km/h, maybe 110 km/h. It's mostly city driving in that country and thus, who gives a damn about a car withstanding an impact?