Slaycation Paradise is the answer to a specific scientific question. That question being, "What if humans gained interdimensional travel capabilities, and were able to travel to alternate worlds?". The answer to said question is not all that surprising. Humanity has a bad habit of destroying their own planet. Of stripping it bare of all resources, and taking more than their fair share from nature. As it turns out the travelers of the future have taken that inherent human greed, and envy to the next level. Looting, and plundering the metaverse, and it's endless array of alternate Earths for fortune and power.
The only thing that stopped them in this pursuit was a ban of moral measures enacted, because of the ramifications of such travel. Through a loophole though humans, as they so often do, exploited the system and turned the advanced technology into a lucrative business endeavor, regardless. Creating Slaycations, or rather violence ridden vacations, for people willing to pay to visit post-apocalyptic worlds in order to kill, steal, and destroy to their hearts' content. All you need is the cash, a boarding pass, some weapons, and the right connections to get you where you want to go. It's a modern family affair where wanton destruction is the reason for that round trip.