Simon could already imagine installing them on various floors of his dungeon and aggravating the adventurers to no end.
That said, there was another thing about the arrays that one needed to know. They cannot be installed just anywhere. To activate an array one needed a stable and powerful source of energy to power them.
As such, it made sense to install them in a place which has a Mystical Vein passing through underneath it. One can also substitute the energy source with mana crystals; however to power even the weakest and the smallest of arrays, one needed tens of thousands of mana crystals above grade [3].
Given how rare and scarce mana crystals above grade [3] was, not just anyone can splurge them on the arrays. But Simon was not just any person, he was the dungeon master of Laplace, an intermediate tier dungeon.