Because when I'm traveling with my kids, the points aren't worth as much as the pint of Haagen-Dazs ice cream they offer. Or at non-FS hotels with a convience store, the offer to let both kids go in and choose any two items they want (which happens more often than not). When I'm traveling alone, I will be much more likely to take the points, but there are situations where the amenity is a nice alternative.