I don't understand why it's such a problem for players to state their opinions or preferences regarding side quests or any quests. (Either for or against) I personally appreciate seeing the reasoning people have for deciding to do or not do a goal or quest, when I'm trying to decide whether or not it's worth doing.
For example, I've decided that particular side goal isn't worth it. Although I have no problem using stored up resources, I also know from experience that as soon as I use up all of a resource, there is usually an urgent requirement for that same resource a very short time later. (Boar pelts, living wood and gold nuggets are recent examples of this.) Therefore, I choose not to sell royal buildings to build more towers and (IMO) waste resources leveling them up all the way to level 5 and also because I find that the towers, and quests like it, are designed to put people in panic mode and create a sense of urgency in hopes that they will spend money to complete them. Look how many players were confused (or maybe fooled?) by the single word "required" dialog pop up that appeared for the tavern side quest.