Yes, I too have to opt out of using this new feature, as it would negate the benefit of my schools (I get so many settlers as loot that I hit capacity and then my schools become useless).
Fortunately, we do have the option to opt out of using this new feature... but it is a shame we can't use the new feature :(
Also because usually when I finish an adventure, it's time to go to bed (on weekdays) and by the time I log on next day, the depleted pop will have been - at least partly - replenished, making it possible to use the rewarded settlers at a later time when I need them right away. Although I solved the problem by keeping the loot in my mail until I need the settlers. :P
The problem here is this is one of those things where one group of players want it one way and another group of players want it another. Personally I would prefer some sort of switch so that I can decide where they go be it mayors or stars as my needs be at that point in time.