Are they gods? Their personalities almost made me picture Ryuk and Rem. I like the dynamics of their relationship, though I believe you ruined it a bit with the
"Tanthos patted his shoulder comfortingly, but he didn't mean it and both of them knew it. There was no lost love between the two, regardless of being brothers." line which unnecesarily spelled what we could infer from their dialogue and also restricted it, stating flat-out that they don't really care for each other (up to then I was still wondering if theirs was just a rough relationship in the surface hiding a strong bond below), something that it would be more interesting to develop through their dialogue and their actions in the following chapters.
I also think the dialogue could use more work to be cohesive. For example, some of their musings hint that they are totally alien to the Earth's workings as they have to search for words and concepts such as "internet" and "amusement park". However, both of them seem to understand clearly the concept of earthly economics as one could presume for the way they address the petty thief affair. Also, both of them use language that is inherently tied to earth's culture such as "drama queen" and "soap opera". Finally, I believe that Thantos' introductory line is a bit weak. When a foreign intelligence observes the humanity and states its veredict I'd expect it to reproach the futility of war, the absurdity of social injustice and the vainty of the pitiful tasks and amusements they keep themselves occupied with, not the rather trivial offenses that he lists.
That being said, I like where it seems to be going, but I advice you not to take mine or anyone's opinion in consideration whether driving it to a conclusion or not. Writing, as all the arts come from the heart. If you love this story and you believe you can take it somewhere, by all means do so, even if in the process the whole world demands you to drop it. On the other hand, if it's just a passing fancy that entertained you for a couple hours and you may or may not feel interested to push it into a finished product, you might as well just drop it and pursue something that really motivates you.
Other people, better than myself, shall give you the advice on fine detail and grammar that I cannot, in all honestly, provide.