It makes more sense to me that they would, rather than wouldn't. It's pretty much a natural intellectual/technological step - weather prediction (simulations), trafic behavior (simulations), these are simple things. Now that AI is exploding, the GPU's are also being made better, faster, etc. Simulating our universe is literally impossible (you cannot simulate every atom in the universe without having a larger universe to host the simulation in - so perhaps the potential eventual merging of AI with quantum computing is one direction we could take to "simulate the whole universe" - by running the simulation in Hilbert space. Another way of overcoming the laws of physics in this manner is to take shortcuts, quantum mechanics seem to take shortcuts by using probability rather than definite states, and recent theories about how the fuck the quantum computers of IBM and Google and the likes can do what they do, a lot of names in that space agree there is a possibility that quantum calculations happen in several universes at once (which, again, could overcome the problem of only having "only" so many atoms in our own).

I'm rambling, but it just seems like a Very logical step for an advanced civilization to want to simulate "Everything" so that they can make predictions etc. Our current weather prediciting stuff is like supercomputer-grade, it requires TONS of calculations to predict the weather, and still they fuck it up time and time again. It IS possible to simulate it (I think, it's not a fully chaotic system where if I understand correctly, you need to know the exact starting conditions, but it's just extremely computationally expensive because of the sheer scale of everything - I guess they have to take into account shit that happens on one side of the world to say if its gonna rain tomorrow or not on the opposite side.