Or you can just not see it as "being forced" to do things but rather punishment for not doing things the optimal way. Yes, you can still do things, you just won't be as well off as you would have been if you put in effort into optimizing. Just like some things in game over time get nerfed or buffed over the course of updates, having all your NPCs stacked in two screen's worth of space has now been nerfed. And "builds like that are impossible" is worst argument ever. It IS optional. Just because there is penalty doesn't stop it from being optional. It's as optional as playing Expert mode. You'll have easier time doing whatever you want, but you will overall get worse rates and some content will be forever locked. Plus, once again, there is such a thing as negligible or near-negligible punishments. Honestly, cost increase is good way to do it because it won't actually affect that much at all, unless you just want to complain about the fact that the increase itself is just there, regardless of whether it has ability to actually make noticable impact or not.
They didn't make normal mode drop rates worse when they added expert mode just to push people to play expert.
How can you say the increase won't be noticeable at all if you don't even know how much it is as the devs have refused to clarify. If they they really intended for an unnoticeable change, they wouldn't have added anything in the first place, it is clearly meant to be noticeable and to push you to build towns "all over the map" as Redigit wants, at the cost of being allowed to build creatively.