Platinum here, 60 nights/year roughly (most in France, Belgium and the Netherlands), would say I do never expect welcome amenities as they are extremely rare.
I usually receive nothing from MGalleries and Sofitels, but the best welcome amenity so far was from an Ibis in Cambridge. Most underwhelming was a single one mini Halloween size chocolate bar on a 2-people reservation in Sofitel Brussels Europe. I'd rather receive nothing if it's to cheap out like this.