Little differences that I´ve noticed:
Many European toilets have two buttons to flush with, one small than the other. The smaller one uses less water. Makes sense.
In the hotel in Bilboa, the lights in the hallway outside the rooms were on a timer, so that they only stayed on long enough for you to get to your room. Less waste of electricity.
It´s difficult getting used to a language, Spanish, in which the lisp is featured so extensively. All that work by speech therapists and gym teachers, beating the lisp out of kids, turns out to be a cultural construct.