Thanos has an obsession with death - in more ways than one. Not only does he crave death itself, but he is also in love with the cosmic entity known as "Death" or "Lady Death" - Marvel's all-powerful Grim Reaper, so to speak. As a result, most of his plans revolve around death in one way or another and, while we can't see the living embodiment of death appearing in the Marvel Cinematic Universe (and therefore no attempts to please her by Thanos will occur), what may happen is that Thanos realises he is unchallenged by the meagre might of the heroes present and, as such, might give up based on the fact that he knows he will prevail. It sounds odd, but that's just what Thanos is about. If he comes to the conclusion that to challenge Earth actually isn't actually "to court death", he might stop in his tracks and move on.
