There are two flaws with that logic.

First, you have to remove them manually, even if you buy them. They would have to implement a different mechanic to not bother you with the chests.

And second, even if you are spending Nutaku gold big time, they are just too expensive and endlessly appearing. I have seen chests costing 700 Rubies. There are better things to spend Rubies on than regularly buying dimensional chests.